The paper estimates the primary market pricing efficiency of China’s IPO after the IPO reform in June 2009, based on the stochastic frontier analysis. The results show that IPO pricing is not fully effective, and discover the existence of “deliberate underpricing”. The average pricing efficiency of China's IPO has reached 0.85, which is close to the level of the mature capital market; To certain extent, we can say that the reform of China's IPO has achieved the initial success. We also found that earnings per share and price earnings ratio are the greatest influencing factors. And there is no underwriter reputation in China. For different markets, we disclosed that, IPO pricing efficiency values in Growth Enterprise Market and Small and Medium Enterprise Board are substantially higher than the Main Board market. The paper analyzes the causes, and then gives some suggestions for the reform of China's IPO.