Objective: Chinese college students' level of health literacy is low, so, we explored the effect of knowledge contests on health literacy (HL) among Chinese college students. Participants: Students from universities in Jiangsu, China. Methods: Two repeated cross-sectional studies were used to compare the effects of the college students' contests. Chi-square tests and variance analysis were used to compare the HL levels and scores, respectively; logistic regression was used for multivariate analysis. Results: The levels of HL after each contest were significantly higher than those in the baseline survey (p < 0.05). There were statistically significant score differences (p = 0.023 and p = 0.001) after the contests in the two studies. Multivariable analysis of HL contest showed that school, grade, profession, completion time, and contest history were statistically significant. Conclusions: HL among Chinese college students was low and it is helpful to regularly hold health knowledge contests to improve these levels, especially for most non-medical students.