Despite the fact that the proportion of part-time workers in the labor force has increased considerably, there have been only a few studies to empirically analyze the work-related attitudes and behaviors of the part-time workers. This study attempted to provide an empirical analysis of differences in organizational commitment between part-time and full-time workers. The findings indicated that:(1) the positive relationship between job tenure and organizational commitment was weaker for part-time workers than for female full-time workers;(2) the positive relationship between organizational climate or leader positive reward behavior and organizational commitment was stronger for part-time workers than for full-time workers; and (3) the negative relationship between alternative job opportunity and organizational commitment was stronger for part-time workers than for male full-time workers.