Background: Studies regarding the effectiveness of CME programmes on physicians' behaviour and communication skills showed inconsistent results. Few randomized controlled trials have been conducted in Asia. Methods: To evaluate the effectiveness of a 4 2-hour education programme to improve GP interviewing behaviours, 16 general practitioners were randomized to the intervention and control groups, respectively. Physicians assigned to the intervention group received 8 hours of training emphasizing interviewing behaviours in the diagnosis and treatment of depression and generalized anxiety disorders (GDS). Those assigned to the control group did not receive any training until the completion of study. Standardized patients were used to evaluate the performance of physicians. Two consultations before and after enrolling in the education programme were videotaped. Independent evaluations of consultations were made by a trained clinical psychologist and a social worker blinded to the study status of physicians. The rating schedule for the videotapes was based on the tasks listed on the Calgary Cambridge Observation Guide. Results: The change of score between the intervention and control physicians was significantly different in 'active listening and facilitating patients' response' (p ¼ 0.011) with the intervention physicians having improvement of score. For 'non-verbals', 'understanding patient's perspective' and 'negotiating mutual plan of action', positive change of score in the intervention physicians were seen when compared to that of the control, although the difference did not reach statistical significance (p ¼ 0.06, p ¼ 0.05, p ¼ 0.06, respectively). However, for 'opening', 'structuring the consultation', 'explanation and planning' and 'closure', there were no statistical significant differences between control and intervention group. Conclusions: Our results showed that only certain communication skills, such as active listening and facilitating patient's response, can be taught in the management of depression and generalized anxiety disorder (GAD) in Chinese primary care physicians.