Objective: To explore the feasibility and effect of the “three-stage” promotion for peripherally inserted central catheter (PICC) maintenance guided by clinical nurse specialist in the street health service center of Wuxi medical partnerships. Methods: For the nursing staff of the street health service center of Wuxi medical partnerships, with intravenous infusion nurses as the main teachers, they should be taken the “three-stage” model of specialized theory training, practical drills and a field guide to promote the PICC maintenance technology. Then the nursing staff of the street health service center should be observed if their theory and operation level have differences before and after the training. Meanwhile, the occurrence condition of PICC complications and patient satisfaction should be compared before and after the promotion of the “three-stage” model in the street health service center. Results: Through the promotion of “three-stage” model, the nursing staff of the street health service center in Wuxi medical partners, the theoretical knowledge and maintenance skills have been significantly improved (P<0.01). The occurrence condition of complications and adverse events in PICC was decreased from 23.08% to 6.25%. Patients were more satisfied with PICC maintenance of Street Health Service (P<0.01). Conclusion: The promotion of the “three-stage” for PICC maintenance guided by clinical nurse specialist can improve the skill level of PICC maintenance of nursing staff in the street health service center, reduce the incidence of catheter complications, improve patient satisfaction, which is finally conducive to the development of primary medical career.