Abstract： Objective:To translate the Dysfunctional Beliefs and Attitudes about Sleep Scale for Cancer Patients (C-DBAS-14) into Chinese and test its reliability and validity.Methods:The Korean version of C-DBAS-14 was translated, back-translated, and culturally adapted into Chinese based on Brislin's translation model, forming the Chinese version of C-DBAS-14. From October 2022 to May 2023, 361 hospitalized cancer patients at the First Affiliated Hospital of Anhui Medical University were selected as research objects by convenient sampling method. They were surveyed using a general information questionnaire, the Chinese version of C-DBAS-14, the Insomnia Severity Index (ISI), and the Hospital Anxiety and Depression Scale (HADS) to evaluate the reliability and validity of the scale. The scale's item analysis was based on correlation coefficients and critical ratio values; structural validity, content validity, and convergent validity were used to evaluate the scale's validity; Cronbach's α coefficient and intraclass correlation coefficient were used to assess its reliability.Results:A total of 361 questionnaires were distributed, 356 were effectively returned, with an effective response rate of 98.6% (356/361). The Chinese version of C-DBAS-14 contained 14 items across four dimensions. The scale-level content validity index was 0.976, and the item-level content validity index ranged from 0.833 to 1.000. Totally four common factors were extracted in exploratory factor analysis, explaining 78.8% of the total variance. Confirmatory factor analysis showed a Chi-square/degrees of freedom ratio of 1.286, comparative fit index of 0.991, goodness of fit index of 0.945, incremental fit index of 0.991, Tucker-Lewis index of 0.988, and root mean square error of approximation of 0.036. The total Cronbach's α coefficient of the scale was 0.874, and the intraclass correlation coefficient was 0.863. The C-DBAS-14 score was negatively correlated with the ISI and HADS scores ( r=-0.734, -0.639; P<0.01) . Conclusions:The Chinese version of C-DBAS-14 has good reliability and validity and can be used as an assessment tool for irrational sleep beliefs in Chinese cancer patients.