Background: To adapt to dramatic changes from physical growth, physical development and the increasing demand of significant others, humor has been found to be an effective coping strategy. However, previous studies have found that adolescents start to express their humor styles with aggressive components which causes negative consequences, such as social anxiety and social loneliness. Therefore, the factors that influence adolescents' humor styles, particularly negative ones, should be of concern. Objective: The purpose of this study was twofold: (1) to investigate the effects of the classroom humor climate and the effects of the personal acceptance of humor messages on adolescents' expressions of humor and (2) to examine how the personal acceptance of humor messages moderates these relationships. Methods: Four types of humor expressions based on the Taiwan Adolescent Humor Instruments were measured: self-deprecating, other-devaluing, body language, and witty response (Chiang et al. in "Psychol Test" 58:179-205, 2011). The current study used a cross-sectional design with data from a nationally representative random sample of 1718 students. The data were analyzed using hierarchical linear modeling. Results: Adolescents' acceptance of humor messages influenced their use of each type of humor, and the classroom climate also modestly influenced their use of humor. When the classroom climate favored self-deprecating/other-devaluing humor, and adolescents more positively accepted self-deprecating/ other-devaluing humor, they engaged in more of that type of humor. Conclusion: Adolescents' acceptance of humor messages should be assessed to identify and reduce maladaptive humor climates and to facilitate a more positive humor style in the classroom by promoting appropriate social norms.