This study aims to determine the effect of self-efficacy, self-esteem, non-physical work environment, and work discipline on the performance of PT KAI DAOP 5 Purwokerto employees. The population in this study were all employees of PT KAI DAOP 5 Purwokerto, totaling 146 employees. The sample in this study used the Probability Sampling method with a purposive sampling technique with a total sample of 117 respondents. Data obtained from respondents with instruments using a questionnaire. The analysis technique uses multiple linear regression. The results of this study based on the F test stated that self-efficacy, self-esteem, non-physical work environment, and work discipline simultaneously have a significant effect on employee performance. based on the t test produces: (a) self-efficacy has a positive and significant effect on employee performance. (b) self-esteem has a positive and significant effect on employee performance. (c) the non-physical work environment has a positive and significant effect on employee performance. (d) work discipline has a negative and insignificant effect on employee performance.