FORM 6-K

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Report of Foreign Issuer
April 5, 2011

Pursuant to Rule 13a-16 or 15d-16 of
the Securities Exchange Act of 1934

Commission file number:  333-12032

Mobile TeleSystems OJSC

(Exact name of Registrant as specified in its charter)

Russian Federation

(Jurisdiction of incorporation or organization)

4, Marksistskaya Street
Moscow 109147
Russian Federation

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F   x   Form 40-F   o

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes   o   No   x

Press release

Mobile TeleSystems Announces Financial Results for the Fourth Quarter and Full Year Ended December 31, 2010

April 5, 2011

Moscow, Russian Federation – Mobile TeleSystems OJSC (“MTS” - NYSE: MBT), the leading telecommunications provider in Russia and the CIS, today announces its unaudited US GAAP financial results for the three months and full year ended December 31, 2010.

Key Financial Highlights of Q4 2010 and FY 2010(1)

·                  Consolidated revenues up 2.9% q-o-q to $2,995 million and up 14.5% y-o-y to $11,293 million

·                  Consolidated OIBDA(2) down 12.0% q-o-q to $1,159 million with 38.7% OIBDA margin and up 8.6% y-o-y to $4,873 million with 43.1% OIBDA margin

·                  Consolidated net income(3) of $156 million in Q4 2010 and a net income of $1,381 million for FY 2010

·                  Free cash-flow(4) positive with $1,529 million for FY 2010

Key Corporate and Industry Highlights

·                  Voluntarily repayment of the second tranche of the syndicated loan in the amount of $161.5 mln; the loan was originally signed in April 2006 and carried a 5-year maturity

·                  Redemption of the $400 mln 2010 Eurobond

·                  Placement of the series 07 and series 08 ruble-denominated bonds totaling RUB 25 bln

·                  Transfer of MTS ordinary shares to the “A1” listing on the Moscow Interbank Currency Exchange

·                  Purchase of 100% stake in Sistema-Telecom for RUB 11.59 bln ($379.01 mln(5)) from Sistema and its wholly-owned subsidiary

·                  MTS recognized as the most valuable brand in Russia with a value of $7.753 bln by InterBrand, the world’s leading brand consultancy

·                  Acquisitions of local alternative operators in Novosibirsk and Saint Petersburg

·                  Signing of an agreement with Sberbank to open two non-revolving lines of credit for a total amount of RUB 100 bln

·                  Suspension of operations in Turkmenistan

·                  Approval of statutory merger of Comstar with MTS by the companies’ respective Extraordinary General Meetings of shareholders

·                  Completion of share buyback in March 2011 related to the statutory merger of Comstar with MTS

·                  Appointment of Andrei Dubovskov, former Head of Business Unit MTS Ukraine, as President and CEO of MTS

·                  Conversion of Comstar ordinary shares into MTS ordinary shares on April 1, 2011 and subsequent completion of the statutory merger of Comstar with MTS

Commentary

Andrei Dubovskov, MTS President and CEO, commented, “2010 was a year of transition for MTS. With the completion of our statutory merger with Comstar last week, MTS has transformed itself from a simple mobile operator to a full-fledged telecommunications provider, offering mobile, fixed, internet and content products and services. For the year, in US GAAP terms, we exceeded our revenue guidance by four (4) percentage points. Revenue increased 14% to 11.3 billion US dollars. Revenues in Russia — including mobile, retail and fixed businesses — increased 12% to 286.4 billion rubles. In our mobile business, growth was driven by: subscriber acquisitions, general growth in consumption of voice and data products, and strong handset sales In Q4 2010, revenue from the sale of handsets, modems and accessories exceeded $276 million US dollars - a 68% increase quarter-on-quarter. The increase was largely driven by the launch of premium handsets and smartphones.”

Alexey Kornya, MTS Vice President and Chief Financial Officer, said “In 2010, Group OIBDA grew by 9% to reach $4.9 billion US dollars. For the year, our OIBDA margin was 43.1%, which is in line with the guidance we gave in April of last year. In Russia, our Q4 2010 mobile OIBDA margin decreased from 45.8% to 37.4% sequentially. We attribute margin deterioration to traditional seasonal factors, such as lower roaming revenues and traditional holiday promotions. However, the margin erosion also was based on certain commercial decisions we made to protect our leadership and stabilize the market.  Higher gross additions increased our spending on dealer commissions. By March, however, we have reduced our sales through alternative channels and aim to see improvement by Q2.  In addition, higher than anticipated handset sales — a 68% rise from Q3 2010 — also pressured our Q4 margins, but based on certain operational KPIs, our retail network did break even for the year. We anticipate margin improvement in 2011 through the optimization of this critical sales channel.”

He added, “In 2010 CAPEX to sales reached 23% or $2.7 billion US dollars as we continued to build-out our 3G and fixed networks in Russia. We expect CAPEX for 2011 to come in at 22-24% as a percentage of revenues. We will be roughly doubling the number of 3G base stations and advancing certain high-profile projects, like the digitization of our fixed-line networks, namely those in Moscow and other large urban centers.”

Continued Mr. Dubovskov, “Obviously MTS has changed, and our financial performance is reflective of this. However, the change has allowed us to create a platform that will usher in a new era for MTS. To date we have been focused on an acquisition model of business. This has served us with the growth of subscribers and the changes in distribution over the years.  Having now established ourselves in both the fixed-line space and retail, we can now begin to focus on retention and loyalty as key operational goals of our business.”

He continued, “Overall, in terms of revenue we see about 10% growth for 2011. We anticipate that Group OIBDA margin will be 42-43% for the year. As we enter the second quarter, we do anticipate that margins will remain pressured. However, we do forecast significant improvement in the second half of the year. We aim to push more tariffs that promote on-net traffic and better monetize off-net calling. Network enhancement will

drive more profitable data usage through our networks. In addition, our ability to launch true convergent products, eliminating redundancy at both MTS and Comstar, will further drive usage and support our churn-reduction efforts.”

This press release provides a summary of some of the key financial and operating indicators for the period ended December 31, 2010. For full disclosure materials, please visit http://www.mtsgsm.com/resources/reports/.

Financial Summary(6)

Russia Highlights

Ukraine Highlights

Uzbekistan Highlights(11)

Turkmenistan Highlights

Armenia Highlights

CAPEX Highlights

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For further information, please contact in Moscow:

Joshua B. Tulgan

Director, Investor Relations

Mob: +7 985 220 4208

Department of Investor Relations

Mobile TeleSystems OJSC

Tel: +7 495 223 2025

E-mail: ir@mts.ru

Learn more about MTS. Visit the official blog of the Investor Relations Department at www.mtsgsm.com/blog/

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Mobile TeleSystems OJSC (“MTS”) is the leading telecommunications group in Russia, Eastern Europe and Central Asia, offering mobile and fixed voice, broadband, pay TV as well as content and entertainment services in one of the world’s fastest growing regions. Including its subsidiaries, the Group services over 108.9 million mobile subscribers in Russia, Ukraine, Uzbekistan, Turkmenistan, Armenia and Belarus, a region that boasts a total population of more than 230 million. Since June 2000, MTS’ Level 3 ADRs have been listed on the New York Stock Exchange (ticker symbol MBT). Additional information about the MTS Group can be found at www.mtsgsm.com.

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Some of the information in this press release may contain projections or other forward-looking statements regarding future events or the future financial performance of MTS, as defined in the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. You can identify forward looking statements by terms such as “expect,” “believe,” “anticipate,” “estimate,” “intend,” “will,” “could,” “may” or “might,” and the negative of such terms or other similar expressions.  We wish to caution you that these statements are only predictions and that actual events or results may differ materially. We do not undertake or intend to update these statements to reflect events and circumstances occurring after the date hereof or to reflect the occurrence of

unanticipated events. We refer you to the documents MTS files from time to time with the U.S. Securities and Exchange Commission, specifically the Company’s most recent Form 20-F. These documents contain and identify important factors, including those contained in the section captioned “Risk Factors” that could cause the actual results to differ materially from those contained in our projections or forward-looking statements, including, among others, the severity and duration of current economic and financial conditions, including volatility in interest and exchange rates, commodity and equity prices and the value of financial assets; the impact of Russian, U.S. and other foreign government programs to restore liquidity and stimulate national and global economies, our ability to maintain our current credit rating and the impact on our funding costs and competitive position if we do not do so, strategic actions, including acquisitions and dispositions and our success in integrating acquired businesses, including Comstar-UTS, potential fluctuations in quarterly results, our competitive environment, dependence on new service development and tariff structures, rapid technological and market change, acquisition strategy, risks associated with telecommunications infrastructure, governmental regulation of the telecommunications industries and other risks associated with operating in Russia and the CIS, volatility of stock price, financial risk management and future growth subject to risks.

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Attachments to the Fourth Quarter and Full Year 2010
Earnings Press Release

Attachment A

Non-GAAP financial measures. This press release includes financial information prepared in accordance with accounting principles generally accepted in the United States of America, or US GAAP, as well as other financial measures referred to as non-GAAP. The non-GAAP financial measures should be considered in addition to, but not as a substitute for, the information prepared in accordance with US GAAP. Due to the rounding and translation practices, US dollar and functional currency margins, as well as other non-GAAP financial measures, may differ.

Operating Income Before Depreciation and Amortization (OIBDA) and OIBDA margin. OIBDA represents operating income before depreciation and amortization. OIBDA margin is defined as OIBDA as a percentage of our net revenues. Our OIBDA may not be similar to OIBDA measures of other companies; is not a measurement under accounting principles generally accepted in the United States and should be considered in addition to, but not as a substitute for, the information contained in our consolidated statement of operations. We believe that OIBDA provides useful information to investors because it is an indicator of the strength and performance of our ongoing business operations, including our ability to fund discretionary spending such as capital expenditures, acquisitions of mobile and fixed operators and other investments and our ability to incur and service debt. While depreciation and amortization are considered operating costs under generally accepted accounting principles, these expenses primarily represent the non-cash current period allocation of costs associated with long-lived assets acquired or constructed in prior periods. Our OIBDA calculation is commonly used as one of the bases for investors, analysts and credit rating agencies to evaluate and compare the periodic and future operating performance and value of companies within the wireless telecommunications industry. OIBDA can be reconciled to our consolidated statements of operations as follows:

(13)  Adjusted OIBDA results for Q4 2009 and Q4 2010 do not include long-lived and other assets impairment loss and acquisition related costs in the amount of $86.4 million and $137.8 million respectively.

(14)  Adjusted OIBDA results for Q4 2009 do not include long-lived assets impairment loss and acquisition related costs in the amount of $86.4 million.

OIBDA margin can be reconciled to our operating margin as follows:

(15)  Adjusted OIBDA results for Q4 2010 do not include long-lived and other assets impairment loss in the amount of $137.8 million.

(16)  Adjusted OIBDA results for Q4 2009 and Q4 2010 do not include long-lived and other assets impairment loss and acquisition related costs in the amount of $86.4 million and $137.8 million respectively.

(17)  Adjusted OIBDA results for Q4 2009 do not include long-lived assets impairment loss and acquisition related costs in the amount of $86.4 million.