Efficiency is one of the fundamental concepts in any organization including ministry of education of Iran. Teachers and counselors are the main assets of this organization and education plays a key role in achieving the organization & apos; s goals. In-service training is a technique for improving the quality and effectiveness of the advisors. This paper presents a study on the effect of in-service training on advisors’ effectiveness through psychological empowerment. The study uses a questionnaire developed by Spreitzer (1995) [Spreitzer, G. M. (1995). Psychological empowerment in the workplace: Dimensions, measurement, and validation. Academy of management Journal, 38(5), 1442-1465.] to examine the effects of five variables; namely self- efficacy, self-determination, impact, meaningfulness and trust. Using structural equation modeling, the study has determined that all five psychological empowerment components had positive and meaningful effects on in-service training. In addition, in-service training maintained positive and meaningful impacts on all components on psychological empowerment. Moreover, in-service training positively influenced on psychological empowerment.