The development of modern defense economics has created severe requirements. The correlation between national defense and economic construction has a new meaning. The relationship between national economic construction and national defense construction can be analyzed via time series econometric method by using the variables of Chinese defense spending, GDP, capital, financial projects, foreign direct investment and international reserve assets. The result findings showed that national defense construction and economic construction are correlated. The main economic variable is both endogenous and exogenous if being combined with defense spending. There is an adjustable long-run equilibrium relation between variables which can serves as reference for policies and measures.