This article examines the concentration of online news sources in China. Using the Gini coefficient as the indicator, this article explores the degree of concentration of online news sources, with the aim of establishing whether online news can be seen as a tool to gain access to a wide range of print and electronic news media. 　　Through a content analysis based on online news （2000 to 2012）, drawn from the Sina News website（ a representative commercial portal in China）, this article confirms that online news sources in China are indeed highly concentrated. 　　The findings of the study can be summarized in four areas. First, it showed that the degree of concentration of the news sources changed over time. It observed a comparatively lower degree of concentration of news sources in 2006. However, after 2006, news sources became increasingly concentrated due to a rigid policy in China’s internet censorship. Second, the study identified differences in the degree of concentration of news sources across news content. News coverage of political issues and social problems showed a comparatively lower degree of concentration, which can be explained by the changes in the censorship of internet and traditional media. Third, it revealed that online news reinforced the concentration of traditional media, by observing consistently high centrality of news sources in Beijing, Guangdong and Shanghai. Finally, it identified the political factor as a key factor influencing the degree of concentration of online news sources. Given China’s firm control on online news websites, this article argues that online news may not yet be an effective mode of gaining access to a diversity of information, and is thus unable to bring about transformative political change in China.