Objective: This study examines the impact of the PC 3-sessions Training Project (PC-project), designed to improve professional competency among social workers in China. Methods: Using a quasi-experimental approach, 170 social workers from social work organizations (SWOs) or community organizations (COs) participated. The experimental group (Group 1), with 127 members, participated in all three sessions; comparison Group 2, with 22 participants, attended the last two sessions; and comparison Group 3, with 21 individuals, participated in the third session. Results: Those who participated in all three sessions improved in four dimensions of professional competency: teamwork skills, community work skills, case management skills, and supportive skills, while the comparison groups showed no significant improvement. In addition, social workers in COs developed their professional competency in more dimensions than those in SWOs. Conclusions: The PC-project is effective in improving social workers' professional competencies; hence, this program should be used in China for training and continuous development.