Teachers' professional satisfaction promotes students' educational success. Studies have shown that teaching in a context of high cultural diversity may affect teachers' level of satisfaction (e.g., satisfaction with students, perceived warmth in the teacher-student relationship, sense of efficacy). This longitudinal study conducted among 69 Canadian elementary school teachers found that those who reported more openness to their students' cultural diversity presented a more positive perception of students and reported greater warmth in their relationships with students but experienced a lower sense of professional efficacy. This study highlights the importance of teachers' openness to cultural diversity, an understudied variable.