Objective To design the self-rating scale on basic ability in graduates of preventive medicine major, and test its reliability and validity, providing a reliable tool for evaluating the basic ability of graduates. Methods On the basis of constructing the Evaluation Index System on Basic Ability in Graduates of Preventive Medicine Major, the three-level indexes were converted to specific questions. Self-evaluation scale including 58 items, 22 sub-dimensions and 8 main dimensions were finally designed after pre-survey and expert argumentation. A total of 205 graduates of preventive medicine major from a medical college and 9 experts in the field of public health were selected to completed the questionnaire. Scale's reliability was tested by applying internal consistency reliability and composite reliability; it's validity was tested by applying content validity and confirmatory factor analysis. Results Scale's α coefficient of internal consistency reliability was 0.976; α coefficient and combination reliability of eight main dimensions were both higher than 0.8; the content validity index S-CVI of the scale was 0.94, the content validity index I-CVI of the item level was 0.78 to 1.00; the average variance extraction amount (AVE) of the eight main dimensions was higher than 0.50. Fitting of the structural model with the item used as observation indexes was reasonable (χ2/df=1.749, RMR=0.036, RMSEA=0.061, NFI=0.801, IFI=0.904, TLI=0.904, CFI=0.903), and the sub-dimension as used observation indexes was good(χ2/df=1.876, RMR=0.032, RMSEA=0.066, NFI=0.913, IFI=0.958, TLI=0.945, CFI=0.957). Conclusion This scale is the first self-rating scale on the basic ability in graduates of preventive medicine major on the basis of the National Standards of Teaching Quality on Public Health and Preventive Medicine, with good reliability and validityl. It is able to achieve quantitative evaluation on graduates' basic abilities. Key words: Preventive medicine; Basic ability; scale; Reliability and validity