The purposes of this study were to explore the effects of mid-level officers' of decision-making style to decision-making behavior, to take this as the future of the reference index for military training or military education, in order to improve the effectiveness of the military organization. The participants were mid-level officers on studying in the National Defense University, including the army, navy and air force class of the 102 years. I applied to Chia-Chun WU (2004) of "leader of the decision-making behavior questionnaire" to measure the implementation of research and analyzed it in spss 19.0 edition. The research showed that mid-level officers in the general decision-making will be showing a robust style, but in the difficulties, even endanger their own interests under the circumstances, they will pursue risk in order to obtain a chance to win, it. In sum, on the order of the mid-level officer concerned, a different decision-making style will result in a different decision-making behavior.