Non-specialist teachers in Canada are increasingly required to teach sexual health topics. However, research suggests that they do not always do so willingly. This study examined the associations between the characteristics of non-specialist elementary and middle school teachers (n = 294) in Canadian schools and their willingness to provide sexual health education (SHE) and their perceptions of factors affecting their willingness to provide SHE. On average, the teachers were only somewhat willing to teach SHE and their willingness varied between topics. The teachers who reported greater willingness to teach SHE were more likely to be teaching middle school, have less teaching experience, have received training to teach SHE, feel more knowledgeable about sexual health, and view broad-based SHE as more important. More than 20% of participants identified 10 out of 11 factors as making them less willing to teach sexual health education; conversely, more than 20% of participants identified nine of these 11 factors as making them more willing to teach sexual health education. Teachers who were middle school teachers, had received training to teach sexual health, had more experience teaching SHE, and felt more knowledgeable about sexual health topics were more likely to regard all of these factors as enhancing their willingness to teach SHE. The results are discussed in terms of their implications for training designed to increase teachers' willingness to teach sexual health. (Contains 5 tables.)