This study aims to determine the influence of supervision on employee performance through discipline as a mediating variable. The number of sample used in this study were 61 respondents who employee of industry and trade ministry of Yogyakarta. Total Sampling was used as a sampling technique. Collecting data technique used is survei method with questionnaire. Path analysis was used as a method of analysis to determine the influence of variable involved. The result showed that supervision has positife and significant effect on discipline, supervision has positife and significant effect on employee performance, and discipline has positife and significant effect on employee performance. The analysis of mediating effect using Sobel test that showed supervision has positife and significant effect on employee performance through discipline as mediating variable.