In this globalization era, The companies are expected to prepare for the new development of technology and the automotive industry which is growing rapidly , because human resources are the main thing to achieving the organization targets. PT Gajah Tunggal Tbk as one of the companies in Indonesia which engaged in the tire manufacturing industry. The Building Department is part of PT Gajah Tunggal Tbk which is required to qualified to the performance indicators that set by the company. The aims of this research was to determined the influence of work discipline, self-efficacy and work environment on employee performance at Building plant D Department at PT Gajah Tunggal Tbk. The research designed uses quantitative methods. Total population was 203 with sized of the sample using the Slovin formula of 134 respondents, processing data analysis using multiple linear regression analysis. The results showed that three (3) variables 'X' had a significant influences on employee performance at PT Gajah Tunggal Tbk, namely work discipline, self-efficacy and work environment. However, there are two (2) variables 'X' which need to be improved by the management of PT Gajah Tunggal Tbk especially in Building Plant D Department namely the work discipline variable and self-efficacy variable. Thus its hoped that management could pay attention to these variables in effort to improve employee performance to achieve the goals, vision and mission of the organization.

Keywords : Work Discipline, Self-Efficacy, Work Environment, Employee Performance.