The aim of this study was to explore the relationship between the quality of student--teacher relationship and attention problems, taking into account two different attention problems (Attention Dysregulation and Attentive Detachment), and the mediating role of Emotion Regulation. Through a multi-informant methodology, teachers rated 161 school-aged children (87 boys and 74 girls) using the "Emotion Regulation Checklist," Teacher's Report Form, and "Student-Teacher Relationship Scale," and observers rated the same children on attentive behavior in class using the "Child' s Attention Scale." Results demonstrated the influence of the student--teacher relationship on attentional behavior, via the mediating role of Emotion Regulation. On dealing with children's attention problems, it will be useful to strive for improving student--teacher relationships that in turn could foster their emotion and attention regulation.