This article selected 177 stocks to analyse the changing performance of the company before and after the Stock Splitting Reform using variance analysis.We discovered that，each stock's net assets does not have remarkable differences subject to change；the index value of each stock's income，property profit margin and the net assets income rate is remarkably higher in the first quarter than previous after the reform；in- dex value in the second and the third quarter are remarkably lower than previous values and there is no remarkable differences between fourth quarter's index value and values before the reform.This conclusion is further carried on with some simple analysis.