This study aims to perpetuate the investigation of organizational commitment and its mediating role as it is one of the most crucial components in understanding organizational behaviour. A total of 324 samples were collected from the academics of 20 private universities in Malaysia. Partial Least Squares Structural Equation Modelling (PLS-SEM) using SmartPLS3.0 was used to perform the latent variable analysis. The results indicate transformational leadership, organizational culture, and organizational justice are the significant predictors of organizational commitment, and organizational commitment, in turn, is found to be a strong predictor of organizational citizenship behaviour. Moreover, the results of mediating analysis highlight that organizational commitment significantly mediates the hypothesized relationship. The implications of the findings are discussed and recommendations for future research are proposed.