The objective of this study is o find out the determinant factors of employee performance and how they affect employee performance variables at the institution. In addition, to find out whether there is a mediating role of citizenship behavior on employee performance in this organization. The population is a group of people who meet the requirements to serve as respondents. In this case, the operations included are all existing BPKS employees, as many as 160 people, both those who work at the BPKS head office in Sabang, as well as those in the representative offices of Banda Aceh, Jakarta, and the island of Aceh. Due to the time limitations of the researchers, not all of the population were used as respondents, but the researchers limited the number of samples to 115 respondents who were obtained using the Slovin formula. Primary data collection was carried out using a questionnaire plus interviews. while data processing was carried out using SPSS software and Amos using the structural equation model (SEM) technique. Of the five direct hypotheses tested, all show a significant effect. The significance that occurs in this direct test indicates that there is a match between the research model developed and the facts at the Sabang Area Concession Agency Office where this research was conducted. Based on the results or findings presented in the previous section, the variables of Organizational Support, Psychological Empowerment, and OCB are indeed the determinant variables of improving employee performance. So that the management can use these three variables as tools or tools to improve the performance of employees at the BPKS Sabang office. To support the strongest increase in employee performance, it can be done through the Psychological Empowerment variable, because this variable has the largest magnitude number compared to the other three variables.