This study investigated the quality of teacher--child interaction and its effects on children's classroom engagement and disaffection in Vietnamese kindergartens. The quality of teacher-child interaction was measured using the Classroom Assessment Scoring System. Children's classroom engagement and disaffection were assessed by Engagement versus Disaffection in Learning. There were 1474 kindergarten children and 60 teachers from 12 kindergartens in three cities in Vietnam participating in the study. The results indicated that classrooms in Vietnam kindergartens had a moderate quality of teacher-child interaction. Compared to the results from other countries published previously, teacher sensitivity and regard for student perspectives of Vietnamese samples were lower than those of Finland, Germany, the United States, and China. Productivity and the instructional learning format in Vietnamese kindergarten classrooms were higher than those of all the other countries except Finland. The results of fixed-effects and random-effects modelling suggested that children in better organised classrooms were more engaged in learning. Emotional support had a negative effect on children's classroom engagement. Children's classroom disaffection was not significantly affected by the quality of the teacher-child interaction.