Kinerja yang optimal merupakan syarat mutlak terpenuhinya tujuan organisasi. Melalui peningkatan disiplin kerja dan lingkungan kerja diharapkan kinerja yang dihasilkan dapat lebih optimal. Masalah yang dikaji dalam penelitian ini yakni adakah lingkungan kerja berpengaruh terhadap kinerja karyawan PT. Pertamina EP Tarakan, apakah displin kerja berpengaruh terhadap kinerja karyawan PT. Pertamina EP Tarakan. Tujuan penelitian ini adalah untuk mengetahui pengaruh lingkungan kerja dan disiplin kerja terhadap kinerja karyawan PT. Pertamina EP Tarakan. Populasi dalam penelitian ini adalah karyawan PT Pertamina EP Tarakan yang berjumlah 80 orang responden. Metode pengumpulan data menggunakan kuesioner, metode analisis yaitu uji instrumen (uji validitas dan uji reliabilitas), uji asumsi klasik, dan analisis regresi linier berganda secara parsial menggunakan SPSS versi 11.5. Hasil penelitian menunjukkan bahwa variabel lingkungan kerja berpengaruh positif terhadap kinerja karyawan dan variabel disiplin kerja berpengaruh positif dan sinifikan terhadap kinerja karyawan. Simpulan dalam penelitian ini adalah lingkungan kerja berpengaruh terhadap kinerja karyawan PT. Pertamina EP Tarakan. Hal ini menunjukkan bahwa hipotesis 1 diterima,. Sedangkan disiplin kerja berpengaruh terhadap kinerja karyawan PT Pertamina EP Tarakan. Sehingga dapat disimpulkan bahwa disiplin kerja karyawan PT. Pertamina EP Tarakan mempengaruhi kinerja pegawainya. Hal ini menunjukkan hipotesis 2 diterima.

Optimal performance is an absolute requirement to achieve the objectives of the organization. By improving the working discipline and working environment, the performance can be optimized. The problem investigated in this research was the working environment which has an influence on the employees’ performance of PT. Pertamina EP Tarakan, whether the working discipline influenced the working performance of the employees of PT. Pertamina EP Tarakan. The objective of this research was to determine the influence of the working environment and working discipline toward the employees’ performance of PT. Pertamina EP Tarakan. The population of this research was the employees of PT. Pertamina EP Tarakan which was consisted of 80 respondents. The method of collecting data was by using questionnaires. The method of data analysis was the validity and reliability test, the classic assumption test, and the partial multiple linear regression analysis in which SPSS version 11.5 was used. The results of the research showed that the working environment had a positive influence on the employees’ performance, while the working discipline had a positive and significant influence on the employees’ performance. The conclusion of this research is that the working environment influenced the employees’ performance of PT. Pertamina EP Tarakan. This shows that the alternative hypothesis 1 (H) was accepted. In the same result, the working discipline also influenced the employees’ performance of PT. Pertamina EP Tarakan. It can be concluded that the working discipline of employees of PT. Pertamina EP Tarakan influenced the employees’ performance. This shows that the alternative hypothesis 2 was accepted.