Objective:To study the influence of objective structured clinical examination (OSCE) assessment mode on learning interest and critical thinking of nursing students in operating room.Methods:There were 49 operating room nursing students from April 2019 to April 2020 who were selected as the observation group, receiving the teaching and assessment mode of OSCE. In addition, 49 operating room nursing students from March 2018 to March 2019 were included as the control group, receiving the conventional teaching and assessment mode. The nursing students' learning attitude scale was used to compare the learning interest of the two groups, and the critical thinking level of nursing students was recorded by Chinese critical thinking disposition inventory-Chinese version (CTDI-CV). SPSS 24.0 software was used to analyze the data with t test and chi-square test. Results:There were statistically significant differences in the scores of learning interest, learning experience, learning habits, professional cognition and the total scores of the learning attitude of nursing students after the assessment between the observation group and the control group ( t=4.861, t=4.885, t=3.466, t=4.206, t=8.292; all P<0.05). There were statistically significance of curiosity, truth seeking, open thinking, analytical ability, systematic ability, self-confidence in thinking, cognitive maturity and the CTDI-CV total scores after the assessment between the observation group and the control group ( t=4.262, t=4.311, t=2.754, t=4.854, t=3.984, t=2.864, t=4.267, t=2.729; P<0.05). Conclusion:The OSCE assessment mode used in operating room for nursing students is helpful to improve the learning interest and the cultivation of students' critical thinking.