Strength-based parenting promotes beneficial outcomes in children's development, including academic achievement. However, few studies have focused on the inner mechanisms underlying the relation between strength-based parenting and students' academic achievement. Guided by life-span development theory, we aimed to examine the mediating role of personal best goals in the relation between strength-based parenting and academic achievement, as well as the moderating role of strength mindsets in the first stage of mediation (between strength-based parenting and personal best goals). An online survey was administered to 273 secondary students in Macau to measure their experiences of strength-based parenting, personal best goals, strength mindsets, and grade point averages. Results indicated that: (a) Strength-based parenting positively correlated with academic achievement; (b) Personal best goals positively correlated with students' perceptions of strength-based parenting and their academic achievement, and partially mediated the relation between strength-based parenting and academic achievement; (c) Strength mindsets moderated the relation between strength-based parenting and personal best goals. For students who had more of a growth strength mindset, the effect of low strength-based parenting on lowering personal best goals was lessened. We further discussed the implications of strength-based interventions and growth mindset training for students' personal growth and academic achievement.