Abstract: Objective To investigate the application of training group in training junior nurses from department of internal medicine. Methods 118 cases of nurses working in the internal medicine less than 5 years were selected as the experimental subjects according to their departments to determine the training objectives and training content, all required target of nurses were qualified as the end of the training. The changes of critical thinking of the junior nurses before and after training, the changes of total points, the evaluation of the doctors and patients to the junior nurses in every job contents before and after training were compared. Results After training, the open-mindedness, seeking truth, systematization capacity, analytical skills, self-confidence, curiosity, maturity and the total score of CTDI-CV of junior nurses were significantly higher than that of before training, which showed statistical significance (P<0.05); the job satisfaction of the doctors and patients to the junior nurses was significantly higher than that of before training, which indicated statistical significance (P<0.05). The results indicated the facts that after training, the examined grade of the theoretical knowledge, professional skills, emergency coordination and communication skills were significantly higher than that of before training with statistical significance (P<0.05). Conclusion Establishing raining group mode in training junior nurses has contributed to the exertion of the various operation skills for the junior nurses, improving the nursing competence so as to avoid the disputes of medical treatment.