The purpose of this study in general is to analyze and describe the significant direct or indirect positive influence of leadership style, supervision and organizational culture on employee performance through motivation as an intervening variable. The research method used is path analysis (part analysis) to determine the direct or indirect effect of the variables studied. To be further used to analyze the extent to which work motivation variables are able to mediate the improvement of the quality of management information systems to improve employee performance and the extent to which work motivation variables are able to mediate the effect of leadership style on improving the performance of Serang District Education and Culture Employees. The results obtained after the research was carried out were: 1) Based on the results of SPSS v.25 calculations, the beta value due to the direct influence of leadership style on performance β=0.000 the indirect effect of motivational mediation factors on the influence of leadership style on employee performance in the Education and Culture Office of Serang Regency was obtained β value = 0.215. Comparison of the direct effect β value is smaller than the indirect effect β value which causes work motivation to be able to mediate the effect of leadership style on employee performance. 2). Based on the calculation results of SPSS v.25, the beta value due to the direct influence of supervision on performance is β=0.155. the indirect effect of motivational mediation factors on the influence of supervision on the performance of employees of the Serang District Education and Culture Office obtained a value of β = -0.046. Comparison of the direct effect β value is greater than the indirect effect β value which causes motivation to be unable to mediate the effect of supervision on employee performance. 3). Based on the calculation results of SPSS v.25, the beta value due to the direct influence of organizational culture on performance is β=0.000. the indirect effect of motivational mediation factors on the influence of organizational culture on the performance of employees of the Serang Regency Education and Culture Office obtained a value of β = 0.243. Comparison of the direct effect β value is smaller than the indirect effect β value which causes motivation to be able to mediate the influence of organizational culture on employee performance