The present study focused on genetic and environmental influences on appreciation of structure and content of humor. Monozygotic (n = 135) and dizygotic (n = 60) adult twin pairs rated their trait-like humor appreciation using the 3 WD humor test (Ruch, 1992) which assesses three basic humor stimuli (incongruity-resolution humor; nonsense humor; sexual humor), and two basic components of responses to humor (funniness; aversiveness). Additionally, two indices were derived from these scales, namely structure preference and liking of sexual content (i.e., controlled for humor structure). Intraclass correlations and behavior genetic model-fitting analyses indicated a moderate genetic effect for funniness ratings of liking the sexual content. The remaining funniness scales seemed entirely influenced by environmental effects. Aversiveness scales mainly showed environmental effects represented in reduced CE models, although twin similarity coefficients showed hints of genetic influences as well, which needs to be unraveled in future research. The results demonstrated clearly that funniness ratings should be separated for structure and content, to obtain detailed information about heritability of humor appreciation. Future research should validate these promising initial findings by utilizing larger samples.