Teachers' continuing professional development (CPD) can improve teacher quality and teaching practice, yet teachers differ greatly in the extent to which they engage in CPD. In extensive research into which factors affect teachers' participation in CPD, the effects of teachers' beliefs have received limited attention, despite their strong influences on people's working and learning. Teachers' beliefs about learning and teaching in particular influence their teaching practices. Does a comparable relationship exist between these beliefs and teachers' own learning or participation in CPD? To explore this relationship, 260 Dutch secondary school teachers completed a survey that focused on the teachers' student-oriented and subject matter-oriented beliefs, as well as on teachers' updating, reflective and collaborative activities. Because teachers' characteristics reflect both belief dimensions, this study relied on cluster analysis, which revealed three distinct belief profiles. These results indicated that teachers' beliefs about learning and teaching relate to their participation in CPD: the more a teacher's profile is student oriented and subject matter oriented, the higher his or her participation in CPD. The results have implications for enhancing teachers' reflections on their beliefs about learning and teaching, in conjunction with participation in CPD.