Think tanks in China simultaneously play advisory, academic and advocacy roles in the policy process. In this article, I recommend an analytical framework that evaluates think tanks by studying their specific activities in addition to their nature. Empirical data involving 301 think tanks in 25 provinces were collected through the China Think Tank Survey 2004. The 1998 regional Integrated Knowledge Development Index database was also used for the analysis. Based on these two independent sets of survey data, the article concludes that connections with the government and knowledge capacity in regions where think tanks are located are the two differing forces that drive China's think tanks to operate as either advisors or advocates. Moreover, these two determinants differentially influence the individual roles of the two types of think tanks.