The self-concept of student-athletes is often challenged. This study aimed to examine the significance of motivational climate and eating habits as predictors of self-concept among senior high school student-athletes. Using multiple linear regression analysis, with 150 student-athletes as selected sample through stratified random sampling, it was found that the determinants are both significant predictors accounting 21.1% degree of influence. The Triadic Reciprocal Determinism Theory was affirmed. Collaborative activities maybe initiated by the educators, coaches, and policymakers to enhance motivational climate and eating habits to benefit the student-athletes self-concept.