The purpose of this research is to investigate the social factors affecting the motivation to commit suicide among soldiers. 251 people committed suicide. They have been selected as a statistical population by purposeful sampling. The method of this research according to the questions and the research problem, the data collection technique is survey and quantitative and their analysis was done through spss software. The unit of analysis in this research is the individual. The data collection tool was a questionnaire. Its theoretical framework is a combination of sociological and psychological concepts. These concepts are suicidal act, social capital and adaptation to society. The research results showed that the lowest age of respondents who committed suicide is ۱۸ and the highest is ۳۳ years, and the average social capital among these people is low. Also, the findings of the research showed that there is no significant difference between education and attempted suicide. According to the findings, it was shown that there is a significant relationship between adaptation to society, social capital and the motivation to commit suicide, this relationship is inverse and negative, that is, with the reduction of social capital and adaptation to society, the motivation to commit suicide increases. And about ۲۲% of the change is related to the motivation to commit suicide due to social capital and adaptation to society. No significant relationship was observed between suicide motive and age. These results were discussed in connection with previous researches.