This study aims to examine the effects of types of brand transgressions and moral reasoning strategies (moral decoupling and moral rationalization) on consumers’ trustworthiness in and attitudes toward an athlete endorser when a brand company that sponsors the athlete commits transgressions. By using a professional research company, 440 individuals were recruited online. The one-way analysis of variance (ANOVA) results reveal that consumers’ trustworthiness of and attitudes toward the endorser are likely to be lower for product transgressions than for moral transgressions. Higher levels of moral decoupling show significantly higher trustworthiness of and attitudes toward the endorser than the middle and lower levels do. To keep an endorser’s image positive, the endorser or his/her agency should carefully consider a sponsor’s history and reputation while selecting a sponsor.