Objective: The conduct of a medical interview is a challenging skill, even for the most qualified physicians. Since a training is needed toacquire the necessary skills to conduct an interview with a patient, we compared role-play with standardized patients (SP) training and aconventional lecture for the acquisition of communications skills in undergraduate medical students. Methods: An entire promotion of third year undergraduate medical students, who never received any lessons about communicationsskills, were randomized into 4 arms: 1) SP 2 months before the testing of medical communications skills (SP); 2) conventional lecture 2months before the testing (CL); 3) two control groups (CG) without any intervention, tested either at the beginning of the study or twomonths later. Students were blindly assessed by trained physicians with a modified 17-items Calgary-Cambridge scale. Results: 388 students (98.7%) participated. SP performed better than CL, with significant statistical differences regarding 5 skills: theuse of open and closed questions, encouraging patient responses, inviting the patient to clarify the missing items, encouraging of the patient’semotions, and managing the time and the conduct of the interview. The SP group specifically improved communications skills betweenthe SP training and testing sessions regarding 2 skills: the use of open and closed questions and encouraging patient responses. Noimprovements in communications skills were observed in CG between the two time points, ruling out a possible time effect. Conclusion Role-play with standardized patients appears more efficient than conventional lecture to acquire communication skills inundergraduate medical students. Psychiatry Investig 2020;17(4):299-305