Internal marketing is growing recognition in these few years. Scholars have recommended that it is positively associated with employee commitment but little empirical research is conducted for educational institutions. Therefore, the purpose of this study is to investigate the effect of internet marketing on organizational commitment and also the mediating effects of customer orientation/ organizational communication between internal marketing and organizational commitment of the administrative staff of the University of Macau. Data were collected from 105 administrative staff in the University of Macau and analyzed using linear regression with the SPSS. Data analysis shown that there was positive relationship between internal marketing and organizational commitment, but no significant relationship existed for the mediators between the internal marketing and the organizational commitment. The result of the study indicated that the University of Macau should instill the internal marketing concept into the management strategy, in order to improve the organizational commitment of the employees.