Abstract: Constructing the standard neo-clsaaical model of the demand for defense expenditure and testing the empirical econometric model of the defense expenditures in China, we estimated demand for militar yexpenditure in terms of economic, security and strategic variables in China for both periods: 1960～1980and 1981～1999. The results suggest that the change of the defense developing doctrine in China between the periods has a most influence to demand for defense expenditures. In 1960～1980, the determaints of demand for defense expenditures are security environments, the defense expenditures are already exceed the economy of acceptance ability. But in 1981～1999, the most influence of factors are lag defensee xpenditure and GDP.