While homework is a frequent source of distress, positive attitudes of parents can help students develop positive emotions and self-efficacy regarding homework. In this study, we tested the hypothesis that parents' emotions, favored by autonomous motivation, directly and indirectly relate with students' emotions through their self-efficacy with regard to homework. Questionnaires were administered to 205 fourth- to eighth-grade students and their parents to assess both groups' positive and negative emotions, students' self-efficacy with regard to homework, and parents' autonomous motivation. The results supported the hypothesized model: parents' autonomous motivation is associated with parents' positive emotions, which is then associated with students' positive and negative emotions, both directly and through the mediation of students' self-efficacy for doing homework. The discussion focuses on theoretical and educational implications.