Strengthening social work personnel training in the period of Republic of China is to promote the China localization of social work, enhance social workers’ occupation specialization and adapt to the needs of society at that time. Therefore, the national government also had attached great importance to social work personnel training, and strived to explore the effective way of constructing “of the Trinity” social work personnel training mechanism from three aspects of legislation, training mode and training method. The construction of training mechanism for training, on the one hand, cultivated a large number of social work professionals, promoted the construction of local social undertakings at that time, on the other hand, it presented characteristics of“mandatory training management, flexibility of training methods, and professional training content.”