Abstract: This article gives statistical analysis the data of mortality of fifteen main diseases of China's residents in 1995,using analysis of variance of factorial design and curve fitting of polynomial combined with SAS software package.It is found that there are very significant differences in Mortalities between urban residents and rural ones、males and females、nineteen age groups and fifteen main diseaes,but there are no significant combinations among city、countryside、male and female,the curve equations age are fitted respectively.The best models are all quintic polynomial.