Objective:To explore the effects of nurse as standardized patient (NSP) in clinical apprenticeship and objective structured clinical examination (OSCE) of psychiatric nursing.Methods:Totally 260 undergraduate nursing students admitted to the School of Nursing of a medical university in 2017 were selected into experimental group, who were taught in combination of real patients and NSP, and received assessment of clinical apprenticeship skills through OSCE involving NSP. Totally 286 undergraduate nursing students admitted in 2016 were selected into control group, who received conventional clinical apprenticeship teaching and assessment. The discrimination and difficulty of the assessment of the experimental group was considered, and the test scores, the degree of recognition of the assessment form by the nursing students, and the ability of critical thinking were compared between the two groups.Results:Totally 247 nursing students in the experimental group and 280 in the control group completed the study. The degree of difficulty and discrimination met the assessment requirements. There was a statistically significant difference in apprenticeship performance between the two groups ( P<0.01) . After OSCE, the recognition scores of the two groups for OSCE were (3.22±0.64) and (4.17±0.58) , respectively, and the difference was statistically significant ( P<0.01) . The total scores of Critical Thinking Disposition Inventory-Chinese Version (CTDI-CV) of the two groups were (278.29±25.66) and (289.53±35.43) , respectively, and the difference was statistically significant ( P<0.01) . There were statistically significant differences in the scores of CTDI-CV in 4 dimensions between the two groups, they are open-mindedness, analytical ability, systematic ability and self-confidence ( P<0.05) . Conclusions:The NSP-based clinical apprenticeship and OSCE for psychiatric nursing is feasible and practical, which can improve students' critical thinking ability, and is worth referencing and promoting.