The purpose of this study  is to find out whether the job characteristics, the transactional leadership and the transformational leadership have influences on the organizational level of commitmnet. This case study was conducted taking as samples the employees of the Central Java-based Supreme Audit Institution.

The sampling technique used was sampling purposive method by applying such questionnaires as : Job Diagnostic Survey for the job characteristics, Multifactor Leadership Questionnaire for the transactional and transformational leadership and Three Components Model Questionnaire for the organizational commitment. Data analysis method used was multiple-linear regression method.

Regression analysis demonstrated that 1) simultaneously the three independent variables have no significant influences on the organizational commitment, 2) partially, the transformational leadership has significant influence on the organizational commitment, 3) the tranformational leadership has predominant influence on the organizational commitment. And on the basis of the results of the regression analysis, the hypotheses proved were 1) the transformational leadership partially has significant influence on the organizational commitment, 2) the transformational leadership has predominant influence on the organizational commitment compared to the job characteristics and the transactional leadership.

Key words : job characteristics, transactional leadership, transformational leadership, organizational commitment.