Objective To investigate the quality of nursing care after the application of tracer methodology in patients undergoing chemoradiotherapy with peripherally inserted central catheters (PICC),evaluate the nurses' adherence to the procedural protocol of PICC,and calculate the number of infectious complications related with the placement.Methods We compared the nurses' adherence to the procedural protocol and the number of infectious complications before (April 2014 to June 2015) and after (July 2015 to October 2016) the tracer methodology was applied at the Chemoradiotherapy Center of Ningbo First Hospital in July 2015.Results After the tracer methodology was introduced to the care of patients with PICC,the nurses had better adherence to the procedural protocol,as shown in the rise of quality control score from (94.00± 3.35) to (97.87± 1.42).The incidence of infectious complications dropped significantly (all P＜0.001).Conclusion The clinical application of tracer methodology can improve the quality of nursing for patients with PICC,reduce the incidence of PICC-related infectious complications,and promote patient safety.