Purpose: This study was examined the effects of a hepatitis A education on attitude, vaccination intention, and preventive behavior. Methods: Eighty-eight college students at two universities participated in this study. The data were collected from August 29 to September 30 in 2011 and were analyzed using descriptive statistics, t-test, and x² test. Results: There were no significant differences of preventive behavior of hepatitis A between the positive and negative message groups (t=1.10, p=.499). However, the negative message group had a significantly higher attitude of preventive behavior (t=0.92, p=.049) and vaccination intention (x²=5.43, p=.039) than the positive message group. Conclusion: This study demonstrates that negatively framed messages are effective on increasing the attitude, vaccination intention, and preventive behavior.