Introduction: Training, in each organistion, may be offered III different forms including in-service education. In-Service education in hospitals is increasing important because of the dynamic of medical Sciences.

Methods: This research was done as a quais i-experimental study, to evaluate a retraining program offered to promote the knowledge of medical record practitioners of a social security hospital in Estahan in fall 1382. There were 30 subjects whose knowledge level was measured by a questionnaire before and after the retraining program. Face validity of the questionnaire was confirmed and its reliability was measured by a pretest and a post - test. The first part of the questionnaire included personal details and the second part consisted of 30 questions related to the subject content offered in the program. Data analysis was done by parametric and non parametric tests with the aid of SPSS soft ware.

Findings: The Percentages of correct mowers, given by the subjects in the pretest and posttest, were 50% and 78%, respectively. The personnel's with an educational background, related to medical education, showed higher scores both on the pretest and the post test. The scores of medical practitioners of Shariati hospital, on both tests, were lower than those of the other two hospitals, Qarazi and Fatemehalzahra.

Conclusion: Considering the significant effect of this retraining program on promoting the knowledge level of the practitioners, it seems essential to offer such a program for all medical record practitioners.