Objective　To explore the application of fuzzy mathematics theory in the evaluation of medical students' comprehensive mental quality. Methods　A total of 80 medical undergraduates studying in the Affiliated Huai'an No.1 People’s Hospital of Nanjing Medical University from October to December 2017 were randomly selected to conduct a questionnaire survey on medical students' mental quality. The questionnaires were designed by the study group

containing 3 first-level items (learning pressure

life stress and interpersonal stress)

and 19 secondary items

with the recovery rate as 95%. Fuzzy comprehensive evaluation method was used for data processing and analysis. Results　By comparing the data obtained from the comprehensive evaluation of the secondary factors with those of the pre-set evaluation set

the study concluded that 25.00% of the medical students need to adjust the future pressure

41.70% the family health status pressure and 26.79% the appearance pressure according to the principle of maximum mem-bership degree. The comprehensive evaluation of the first four factors (0.249 7

0.268 9

0.270 2

and 0.211 2) showed that the comprehensive mental quality of medical students was good. The quantitative analysis results showed that 27.02% of the medical students had good comprehensive mental quality

24.97% need the mental quality adjustments

26.89% had the average mental quality

and 21.12% had outstanding mental quality. Fuzzy comprehensive evaluation indicated that it is necessary to adjust the learning pressure and life stress of medical students

while the interpersonal stress had little effect on the mental quality of medical students. Conclusion　The fuzzy comprehensive evaluation adopts the quantitative method to deal with the qualitative indicators uniformly

being scientific and reasonable. The corresponding data of each indicator can be easily identified with the help of the indicator system built up in the evaluation

which provides evidence for distinguishing and improving the corresponding decision-making for improving the medical students' mental quality. This evaluation method has strong applicability and provides new methods and ideas for objectively evaluating the comprehensive mental quality of medical students.