Introduction: Professional ethics in Rehabilitation Sciences is necessary for achieving therapeutic goals. Considering the importance of professional ethics training for rehabilitation students, we aimed to investigate the effects of a professional ethics workshop on improving the students’ ethical knowledge at Ahvaz Faculty of Rehabilitation Sciences, Ahvaz City, Iran.Materials and Methods: This quasi-experimental, cross-sectional study was conducted on all third- and fourth-year students in Audiology, Physiotherapy, Occupational therapy, and Speech therapy and the postgraduate students of the faculty. The two-day workshop was held for 16 hours. The students completed an ethical knowledge assessment test designed by the faculty members before and after the workshop.Results: The data of 206 students (26% male and 74% female), with a mean age of 25.68 years, were analyzed in this study. The Mean±SD scores of the ethical knowledge test before and after the workshop were 4.71±1.84 and 7.02±1.42, respectively. Based on the results, the ethical knowledge of the students increased significantly after the workshop (P<0.001). Improvement of ethical knowledge scores was significantly different between educational levels (P=0.033). Also, the improvement of ethical knowledge score was significantly different among various study fields (P=0.007).Conclusion: Considering the promotion of students’ ethical knowledge through participation in this workshop, it is suggested that an ethical workshop be held upon the entry of all rehabilitation students into the clinical field.