PURPOSE: This study was examined to identify the relationship among knowledge, attitude, and compliance with preventive behavior on influenza A (H1N1) by University students. METHODS: The sample consisted of 101 students. The data were collected from August to September 2009 and analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficients, and stepwise multiple regression. RESULTS: The mean scores of knowledge (11.89 +/- 1.39), attitude (30.16 +/- 2.87), and compliance with preventive behavior (22.35 +/- 3.51) on influenza A (H1N1) were above the average. The level of knowledge was not significantly different regardless of characteristics. Students' attitude differed according to gender (p<.001), and plan to seasonal influenza vaccination for this year (p=.007). Compliance with preventive behavior was significantly different according to experience of seasonal influenza vaccination during last year (p=.010), experience of obtained information about influenza A (H1N1) (p=.037). Significant correlations were found between knowledge and compliance with preventive behavior (p<.001), attitude and compliance with preventive behavior (p<.001). Knowledge and attitude was a predictor of compliance with preventive behavior (23.4%). CONCLUSION: These findings indicate that perceived knowledge and attitude may be necessary to improve compliance with preventive behavior on influenza A (H1N1) among university students. The results of the study can be utilized in educational programs about preventing the occurrence of influenza among university students.