At present, the industrial agglomeration of national defense science and technology industry shows a trend of in-depth development. However, from the perspective of the actual situation of each province, there are still some problems such as low degree of industrial chain remodeling, small scale of industrial agglomeration, unbalanced product production and imperfect policies and systems. Based on Marx's theory of division of labor and cooperation, it is found that the existing problems in the industrial agglomeration of national defense science and technology industry in China are mainly caused by the low degree of specialized division of labor, incomplete division of labor and the division of military and civil goods. Therefore, it is suggested that we should optimize the cluster development of national defense science and technology industry on the basis of specialized division of labor, on the basis of cooperation, on the basis of backbone enterprises and on the basis of policies.