The performance of personnel of KODAM I / Bukit Barisan communications unit is influenced by many factors. This research analyzes the influence of Leadership, Work Discipline, and Organizational Commitment to Personnel Performance either partially or simultaneously. Population in this research is personnel of transportation unit KODAM I / Bukit Barisan which amounted to 78 personnel. Because the population in this study is less than 100 people then in this study the sampling method using the census method, meaning that all the population sampled in this study. The technique of data analysis using multiple linear regression equation, and continued by testing R Square and hypothesis testing partially and simultaneously with t test and F test. Data analysis tool with SPSS application 23.00. The results showed that Leadership, Work Discipline and Organizational Commitment have positive and significant effect on Personnel Performance either partially or simultaneously. From the results of determination analysis there are other factors that influence the performance of personnel in addition to variables Leadership, Work Discipline and Organizational Commitment. The better the leadership, the Work Discipline and the Organizational Commitment, the better the performance of the personnel of the KODAM I / Bukit Barisan communications unit.