SINA SINA com

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

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Exhibit 99.1

SINA Announces Agreement with CEO for US$456 Million Cash Investment

SHANGHAI, June 1, 2015—SINA Corporation (NASDAQ: SINA) (“SINA” or the “Company”), a leading online media company serving China and the global Chinese communities, today announced that it has entered into a legally binding subscription agreement with Mr. Charles Chao, Chairman of SINA’s board of directors and Chief Executive Officer, for the issuance and sale of 11,000,000 newly issued ordinary shares of the Company to Mr. Chao. Pursuant to the agreement, Mr. Chao will subscribe for and purchase directly or through a special purpose vehicle beneficially owned and controlled by him, 11,000,000 newly issued ordinary shares of SINA for a total purchase price of approximately US$456 million in cash. The per share purchase price of US$41.49 represents the average closing trading price of SINA’s ordinary shares for the 30 trading days ended May 29, 2015 and is higher than the closing trading price on May 29, 2015, the last trading day before the signing of the subscription agreement. Mr. Chao has agreed to subject all the shares he or his affiliate will acquire in the transaction to a contractual lock-up restriction for six months after the closing. The closing is expected to take place upon satisfaction of customary closing conditions.

About SINA

We are an online media company serving China and the global Chinese communities. Our digital media network of SINA.com (portal), SINA mobile (mobile portal and mobile apps) and Weibo (social media) enables Internet users to access professional media and user generated content in multi-media formats from desktop personal computers and mobile devices and share their interests with friends and acquaintances.

SINA.com offers distinct and targeted professional content on each of its region-specific websites and a full range of complementary offerings. Our mobile portal, SINA.cn, provides news information and entertainment content from SINA.com customized for mobile users in WAP (mobile browser) and mobile application format. Weibo is a leading social media platform for people to create, distribute and discover Chinese-language content. Based on an open platform architecture, Weibo allows users to create and post feeds up to 140 Chinese characters and attach multi-media content, as well as access a wide range of organically and third-party developed applications, such as online games.

Through these properties and other product lines, we offer an array of online media and social media services to our users to create a rich canvas for businesses and advertisers to effectively connect and engage with their targeted audiences.

Safe Harbor Statement

This press release contains forward-looking statements. SINA may also make forward-looking statements in the Company’s periodic reports to the U.S. Securities and Exchange Commission, in its annual report to shareholders, in press releases and other written materials and in oral statements made by its officers, directors or employees to third parties. Statements that are not historical facts, including statements about the Company’s beliefs and expectations, are forward-looking statements. These forward-looking statements can be identified by terminology such as “will,” “expects,” “anticipates,” “future,” “intends,” “plans,” “believes,” “confidence,” “estimates” and similar statements. SINA assumes no obligation to update the forward-looking statements in this press release and elsewhere. Forward-looking statements involve inherent risks and uncertainties. A number of important factors could cause actual results to differ materially from those contained in any forward-looking statement. Potential risks and uncertainties include, but are not limited to SINA’s limited operating history in certain new businesses; condition of the global financial and credit market; the uncertain regulatory landscape in China; fluctuations in the Company’s quarterly operating results; the Company’s reliance on online advertising sales and value-added services for a majority of its revenues; failure to successfully develop, introduce, drive adoption of or monetize new features and products, including portal, Weibo and MVAS products; failure to enter and develop the small and medium enterprise market by the Company or through cooperation with other parties, such as Alibaba; the Company’s reliance on mobile operators in China to provide MVAS and changes in mobile operators’ policies for MVAS in China; failure to successfully integrate acquired businesses; risks associated with the Company’s investments, including equity pick-up and impairment; and failure to compete successfully against new entrants and established industry competitors. Further information regarding these and other risks is included in SINA’s annual report on Form 20-F for the year ended December 31, 2014 and other filings with the Securities and Exchange Commission.

Contact:

Investor Relations Department

SINA Corporation

Phone: (86-10) 5898-3336

Email: ir@staff.sina.com.cn