The impact of organizational commitment on employees’ job performance has been studied extensively in the West, while few studies have been conducted in non-western countries. Moreover, there are not many studies about the effects of job satisfaction on this relationship. The purpose of this research is to study the effect of organizational commitment on job performance through the mediating role of job satisfaction. For the purpose, four hypotheses were developed, the first three predicted positive relationships between organizational commitment, job satisfaction and job performance and the last one suggested the mediating effect of job satisfaction. 547 employees in Vietnamese enterprises were surveyed. The results of the study supported all the hypotheses. Accordingly, organizational commitment had a positive impact on job performance; organizational commitment had a positive impact on job satisfaction; job satisfaction had a positive impact on job performance when organizational commitment was controlled. The strength of the relation between organizational commitment and job performance was significantly reduced when job satisfaction was added to the model, suggesting the mediating role of job satisfaction. In the light of the findings, it is suggested that merely positive relationship between organizational commitment and job performance may not automatically lead an employer to achieve the outcome - job performance. Therefore, the secret of success lies in improving job satisfaction through solutions to enhance organizational commitment, thereby increase job performance.