Objective:To conduct simulated graduation skill assessment and annual skill assessment by self-designed objective structured clinical examination (OSCE) for standardized training of radiation oncology residents.Methods:The structured examination, standardized questions and standardized tasks of each disease were designed by teaching team of radiation oncology in the University of Hong Kong-Shenzhen Hospital. The implementation effect of the annual assessment and simulated completion assessment of standardized training for residents in radiation oncology from Class 2019 to 2021 was prospectively observed. The difference between scores by two independent examiners was analyzed by the paired t-test. The overall feedback of residents and examiners for the implementation were collected after the completion of OSCE. Results:A total of 18 residents participated in 67 sessions of 3-station skill assessments of different diseases, including 2 make-up tests. There was no difference in the score pairing and grade pairing tests between two examiners at 3 stations ( t=0.85, -0.68, -1.16; P=0.401, 0.499, 0.255). A total of 91.3% of the residents reported that the assessment well reflected their actual clinical competency. Conclusions:The current program of OSCE assessment for radiation oncology meets objectification, standardization and high efficiency, and achieves the goal of making trainers familiar with the graduation skill assessment and assessing comprehensive clinical competence. It is a reproducible and flexible structured assessment model.