This study analyzed children's generalized perceptions of teacher interpersonal behavior in terms of two dimensions, control and affiliation, referring to the degree of teacher leadership/ management and teacher friendliness friendliness/cooperation in the classroom, respectively. An adapted version of the Questionnaire on Teacher Interaction was developed for children ages 6-9. The association between teacher interpersonal behavior and mathematics achievement was investigated by analyzing data from 828 first and second graders in 40 classes across 24 primary schools in the Netherlands. Results revealed the presence of the two interpersonal dimensions with acceptable reliability. Multilevel regression analyses indicated that teacher control and affiliation were positively associated with mathematics achievement, after controlling for mid-year achievement. Control and affiliation each had a partially unique contribution. A differential role of affiliation, but not of control, was found across classes. Our results provided evidence that child perceptions of teacher's control and affiliation are important predictors of early academic achievement. (Contains 5 notes, 5 tables, and 1 figure.)