On the premise that stock price changes are sensitive to ownership structure and financial performance, this study takes A-share manufacturing listed companies in the first half of 2008 as its sample, and uses 300 sets of data to test and verify the influence that ownership structure and financial performance could exert on the fluctuation of stock price. Adopting a cross-section regression method, the regression equation is established, allowing for the characterization of the correlation between ownership structure, financial performance and stock price changes. Three main subjects are studied here. First, this study examines the influence of ownership structure on the stock price changes of listed companies. Second, it considers the existence of the sheep flock effect. Third, it looks at the influence of financial performance on the stock price changes of listed companies. In this research, the author firstly sets up the evaluation indicator system. Here, the indicators chosen reflect ownership structures and financial performance, as these concern investors the most. Secondly, the author processes the data collected, and applies the Pearson-correlation test to check the data. For those items that are not correlated in the Pearson test, the Spearman test and Kendall’s Tau-b test are applied for checking the data. A regression formula will be set and data will be tested for significance. Finally, the author explains the empirical results obtained. By so doing, the author seeks to prove that: 1) with the exception of change in institution equity percentage indicator, the other stock structure indicators are not correlated to changes in stock prices. 2) China’s stock market has not yet been at semi-strong form efficiency, and the sheep flock effect does exist. 3) The changes in stock prices and financial performance indicators are significantly correlated to each other. Whilst it seems arbitrary to assert the non-existence of functional-fixation, yet a few opponents do contend that investors are only concerned by accounting income indicators. Besides net profit growth, the ROE in 2008 model is also proven to be positively correlated to stock price changes. This suggests that some investors in China do accept value-based investment. The conclusions of this paper make a contribution to testing the acceptance of the value investment idea, plus identifying the ability and efficiency of investors’ ability in China’s stock market. Furthermore, it demonstrates that it is also helpful for the government to macro-regulate the capital market. Key Words: ownership structure; financial performance; stock price changes; correlation analysis