To verify the validity of functional health literacy scale and analyze what influences functional health literacy.Using convenience sampling method based on cross-sectional data to select 589 left-behind senior high-school students in an ethnic minority area, using the functional health literacy scale.The scale results were relatively strong, and the absolute fitness index, value-added fitness index, and simple fitness index reached the fitness standards. The overall functional health literacy score was (0.65 ± 0.12), which falls within the upper middle class. Gender(t = 2.40, P < .05), ethnicity (t = 4.28, P < .001), place of residence (t = = 4.51, P < .001), mother's education level (F = 3.608, P < .05), self-assessment of grades for 1 year (F = 25.781, P < .001), and whether the participant liked the health education content (F = 9.416, P < .001) had impacts on overall functional health literacy.The study results show that relatively satisfactory reliability and validity and can be applied further analysis for improving students functional health literacy levels.