Objective To investigate trainees′ transfer of training after PICC standardized training and the influencing factors at different time points, and to provide evidence for promoting sustainable application of PICC. Methods Convenience sampling method was adopted to include 30 nurses who had joined the PICC standardized training program, and the demographic questionnaire, the Transfer of Training of Nurse Scale, and the influencing factors questionnaire were used to survey the nurses at 1 month, 3 months, and 6 months after training. Results The transfer of training at 1 month, 3 months, and 6 months after training were (23.00±2.20), (16.00±2.20), （15.50±1.46） points respectively.The scores for the influencing factors of "managerial support" and "validity of the training program" showed a descending trend over time （P＜0.01 for all）, and the scores for the influencing factor of "hindrances in the organization" showed upwards trend over time （P＜0.01 ）. Conclusion Trainees′ transfer of training after PICC standardized training tails off over time, and the influencing factors also show some patterns .Hence, it is necessary that administrators take targeted measures to push further sustainable and standardized use of PICC.