This study examined the interconnections between perceived teacher support, student selfregulation, and psychological well-being among undergraduate English majors in Iran (n = 347). Confirmatory factor analysis (CFA) validated the measurement model, demonstrating sound internal consistency as well as convergent and discriminant validity. Harman's one-factor test ruled out significant common method bias. Structural equation modeling (SEM) supported the proposed model, revealing a direct positive influence of perceived teacher support on psychological well-being. Moreover, teacher support indirectly enhanced well-being by fostering self-regulation skills. Measurement invariance analyses across genders confirmed configural and metric invariance, suggesting equivalent model structure and factor loadings. However, partial scalar invariance indicated potential minor gender-based differences in interpreting the measures. These findings highlight the significant relationships between teacher support, student self-regulation, and psychological well-being within the Iranian English major context.