Objective To translate the Critical Thinking Diagnostic of frontline nurses （CTDfn） into Chinese and to evaluate its reliability and validity, aiming to provide a tool for assessing critical thinking ability of clinical nurses.Methods The Chinese version of the CTDfn was developed through translation, back-translation and cultural adaption following the Brislin translation model.Then, a convenience sample of 242 frontline nurses were investigated to test the reliability and validity.Results The Chinese version of the CTDfn included 5 dimensions of problem recognition, clinical decision making, prioritization, development of plan of care, and plan of care implementation and improvement, totaling 16 items.Exploratory factor analysis identified 5 factors, explaining 86.472% of the total variance.The Cronbach′s alpha coefficient of the total scale was 0.969, the split-half reliability was 0.925, and the test-retest reliability was 0.835.Conclusion The Chinese version of the CTDfn has good reliability and validity, and it can be used to assess critical thinking ability of clinical nurses in China.