There is abundant evidence to suggest that students' achievement goals (AGs) predict their motivation and performance. While it has been proposed that psychological need satisfaction (PNS) may affect AG, empirical support remains limited during the transition to secondary school. This prospective study addresses this gap by examining the link between students' PNS and AGs through their academic and social adaptation during this transition. A large stratified sample of 626 students completed a series of measures before and after the transition to secondary school. The results revealed that satisfaction of students' needs for autonomy and competence predicted the adoption of mastery goals through their academic adaptation. The satisfaction of needs for autonomy and relatedness also predicted lower adoption of performance-avoidance goals via their social adaptation. These findings highlight the importance of PNS in shaping adaptation and AG during the transition to secondary school. Practical implications for parents and teachers are discussed.