Abstract: Objective：To explore the relationship between the environmental humidity and the stability in various parameters regarding the tear film of the yong people. Methods：209 patients aging from 17 to 35 years old (417 eyes), 133 male patients (265 eyes) and 76 female patients (152 eyes) were enrolled in this study from October 2015 to December 2016. Average age was (22.47±4.74) yeras old. According to the different environmental humidity during their treatment, they were divided into 3 groups: environmental humidity＜40% was taken as low humidity group, 76 patients(151 eyes); that between 40%~70% was taken as middle humidity group, 75 patients (150 eyes); and that >70% was taken as high humidity group , 58 patients (116 eyes). Keeping the patients staying under the specific environment for 1 hour respectively, and then consulting them regarding the dry eye questionnaire, and measure the average breakup time in non-invasive tear film, the height in non-invasive tear meniscus, the score in lipid layer and the lacrimal secretion test with Keratograph ocular surface synthesis analyzer, three sets of different data were analyzed by one way ANOVA. The difference between the parameters under different environmental humidity was analyzed. Results：The analysis resulting from the dry eye subjective questionnaire indicated that the grading result of high humidity group respectively was (1.37±1.52) s, which was lower than that of the low and middle group, (2.27±2.11) s and (1.97±1.82) s, the difference between two groups had statistical sense (P< 0.05). The breakup time of tear film in the low humidity group was (10.67±4.41) s, which was shorter than the other two groups (［12.42±4.47］ s and ［12.81±5.32］ s), the difference both between these three groups (P=0.001，P<0.001) were with statistical significance. The results of the height in non-invasive tear meniscus among the high humidity group was ( 0.24± 0.06) mm, higher than the other two groups which were (0.24±0.07) mm, (0.26±0.06) mm, respectively. The difference between three groups（P<0.001，P=0.017） were statistically significant; the lipid layer grading results of the low humidity group was 1.43±1.28, higher than the other two groups (0.51±0.95 and 0.36±0.91), both the difference between groups (P<0.001，P<0.001) were statistically significant. The fluorescein stain score of the three groups respectively was 0.09± 0.36, 0.05±0.21, and 0.03±0.16, the differences among the three groups were all out of statistic significance. The lacrimal secretion test results of the three groups respectively was (17.65±8.81) mm, (19.13±9.53) mm, and (18.94± 9.62) mm, and the difference among the three groups had no statistic significance. The difference among the three groups of the lacrimal secretion test had no statistic significance. Conclusions：The stability of the tear film is closely related to the environmental humidity, the higher the humidity is, the better stability the tear film has. When the humidity is more than 40%, the stability of the tear film will be maintained in the breakup time of the tear film and the scores in the lipid layer.