Background Despite the focus of many global education systems on science, technology, engineering, and mathematics (STEM) education, research on teachers' concerns about this relatively new educational phenomenon remains scarce. Purpose This study used the concerns-based adoption model as the theoretical framework to examine the primary concerns expressed by teachers about STEM education and identified a typology of teachers based on the response patterns of their concerns. Sample A regionally representative sample of 331 primary and secondary school teachers of STEM-related subjects in Hong Kong participated in this study. Design and methods Data were collected from the teachers through an online, self-reported survey. Latent class analysis was used to profile teachers' concerns about STEM education in this study, and multinomial logistic regression analysis was performed to regress the latent class outcome variable on the covariates. Results The majority of the teachers reported high levels of concern at all five stages of STEM education implementation, namely evaluation, information, management, consequence, and refocusing. Latent class analysis revealed three classes of teachers who were extremely concerned (49.1%), considerably concerned (43.5%), or moderately concerned (7.4%) about STEM education. Multinomial logistic regression analysis indicated that the teaching sector (primary or secondary) and participation in STEM education training significantly contributed to the prediction of the latent class outcome variable. Conclusion Given that 96% of the teachers in this study were trained in STEM education through workshops, seminars, courses, and trips, these findings highlight the necessity of designing personalized professional learning experiences for teachers and provide empirically supported evidence to indicate teachers' preparedness and readiness to adopt STEM education as an educational innovation and directions for future research in related areas. This