This study aims to reveal the moderating effects of academic self-concept on the relationship between academic achievement and career adaptability among junior high school students in Depok City, West Java, Indonesia. With a sample of 662 students, career adaptability was measured using the modified Career Adapt-Abilities Scale, academic achievement with students' average fifth-semester grades, and academic self-concept using the modified Academic Self-Concept for Adolescence Scale. The results showed no significant moderating effect of academic self-concept on academic achievement and career adaptability. It means the strength of the relationship between academic achievement and career adaptability was not affected by student's academic self-concept either positive or not. Based on this study, regardless of their academic achievement and academic self-concept, junior high school students need the optimal available career development preparation to develop their career adaptability.