Purpose: This study was carried out to find out the factors affecting on organizational commitment of hospital nurses. Method: The questionnaire-based research was done with 989 hospital nurses between January and March, 2004. Results: Variables such as job satisfaction, met expectations, compensation and welfare status of hospital, work involvement, positive affectivity had significant positive direct effect on organizational commitment in order of size, however, vertical conflict and job opportunity had negative direct effect in order of size. It was found that the following variables, listed in order of size, had significant total effects on organizational commitment: job satisfaction, met expectations, vertical conflict, compensation and welfare status of hospital, positive affectivity, work involvement, job opportunity, job autonomy, work definiteness, division justice, stability of employment, expectations before entering a hospital. Conclusion: It is recommended that programs for job satisfaction promotion, met expectations promotion, adequate compensation and welfare of hospital, work definiteness and work autonomy, solving conflict, positive affectivity promotion should be implemented to increase organizational commitment of hospital nurses.