Teachers with gender stereotypes are particularly likely to engage in gender-biased teaching practices and to transmit biased gender norms to students. Examining teachers' gender stereotypes is important for understanding gender transmission in schools and gender inequality in educational attainments. Using data from a questionnaire survey of junior high school teachers in the Kansai area of Japan, this study empirically examines teachers' gender stereotypes, focusing on their gender role attitudes. Using latent class analysis to examine teachers' gender role attitudes, the results identify three patterns (gender equality supporters, care-gender role supporters, and gender role supporters) in teachers' gender role attitudes. The distinctive pattern is the care-gender role supporters, a group that rejects some traditional gender roles but is more likely to hold the gender stereotype that women are better suited for housework and childcare; this group is considered "potential" gender stereotypes. Furthermore, using a latent class multinomial-logit model, we test three hypotheses regarding gender, age, and teachers' subject. The results show that the hypotheses are partially supported and that teachers' gender role attitudes are influenced by the basic factors mentioned above, including the interaction effect. Based on these findings, we discuss the structure of teachers' gender role attitudes and suggest the importance of focusing on teachers with potential gender stereotypes.