Abstract: Based on the DSSW model and the theory of noise trading,this article introduced market style and mood index variables,and built the measurement model of investor behavior risk,and explored the correlations between the behavior risk of stock market investors and asset prices,risk-free interest rate,the dividend of risk assets,risk aversion coefficient,the market expected price,the proportion of rational investors,investor sentiment index,the amount of risk assets held by rational investors,and the wrong cognitive of noise traders,and the correlations between the style of the stock market and investor behavior risk. Theoretical analysis show that,in the ordinary circumstances,noise trading behavior possessed the mood infection and amplification effect,and holding more risk assets and price pressure effect,and market style and risk assets preferences,and behavioral coincidental effect.