Abstract: The fluctuation of real estate market will perplex other sections and even the whole national economy. Therefore, the early warning of this fluctuation is very important. Combining the method of forecasting through statistical fitting and the 6-sigma early warning method, this paper selects key indexes of price, sales volume, investment and coordination degree in Shanghai’s real estate market to fit into the established model. The result shows that there is difference in the price affection model among several sub-markets in Shanghai. While the comparative price ratio of outside-ring district was mainly related with sales rather than investment factors, the comparative price ratio of inner-middle districts was more related with the matter of supply-demand and reasonable investment ratio. Thus, we can make respective forecasting models, alarming statistics, and early warning control charts reflecting the reality.