This paper reviewed the relationship between job demands and safety motivation, and the moderating effect of A-type trait in Korean Air Force. Based on the responses from 722 responses, the results of multiple regression analysis appeared as follow; 1) role overload effects positively and role ambiguity effects negatively on intrinsic safety motivation. 2) role conflict effects negatively on extrinsic safety motivation. 3) role ambiguity effects negatively on intrinsic safety motivation in B-type than in A-type trait.