Fear appeal's effects on advertisement responses were studied often. Self-efficacy was also researched together with fear appeal as a moderator frequently. But there has been no research examining fear appeals' effects on individuals' self-efficacy. Moreover, even though there were some studies investigating humor appeal's effects on information processing and persuasion, none of them incorporated fear and humor appeal in the same study or tested the interaction of fear and humor on self-efficacy or message acceptance. This study examines the interaction of fear and humor on individuals' self-efficacy, attitude and behavioral intention, using the drinking and driving topic. An online experiment was conducted with 230 participants. The results showed that all hypotheses were rejected. Since the humor manipulation also failed, the results mean fear and humor's interaction on the influence of self-efficacy were not found. Their effects on attitude and behavioral intention were not demonstrated either. Then this study talks about alternative explanations of the failure of the hypotheses tests, from theoretical and methodological perspectives.