This study aimed to validate a systematic instrument to measure online players' motivations for playing online games (MPOG) and examine how the interplay of differential motivations impacts young gamers' self-concept and life adaptation. Confirmatory factor analysis determined that a hierarchical model with a two-factor structure of Social-engaging and Social-disengaging MPOG has better factorial validity than one-factor and two-factor models. The study found that individuals who play online games with Social-engaging MPOG are more likely to have a healthy self-concept and life adaptation, whereas players who have Social-disengaging MPOG have poorer self-concepts and experience a significant, negative, and indirect effect on life adaptation through their self-concept.