This study aims to test core self-evaluation, workload, and workplace spirituality influence on the PT Bank Aceh Syariah-Operational Head Office (BAS-OHO) employee performance with a career commitment as a mediator. The population was 189 and it used census techniques for sampling. Data were analyzed via one sample t-test, Structural Equation Modeling (SEM)-AMOS, and Sobel test. The test results conclude that in BAS-OHO, the core self-evaluation, workplace spirituality, career commitment, and employee performance were running well, while the workload felt by employees was already in a high position. Then, core self-evaluation and workplace spirituality influence career commitment and BAS-OHO employee performance positively, but Workload influences career commitment and BAS-OHO employee performance negatively. Furthermore, career commitment itself also influences BAS-OHO employee performance, and Career commitment partially mediates the core self-evaluation, workload, and workplace spirituality influence BAS-OHO employee performance. These findings explain that the BAS-OHO employee performance improvement model is a function of strengthening core self-evaluation, adjusting workloads, strengthening workplace spirituality, and strengthening career commitment.