This study was intended to investigate the differences of job stressors and job stress among white-collar workers, blue-collar workers, and professional research workers. Another objective of this study was to examine whether the effects of job stressors on job stress differ among the three groups. Data were obtained from 893 white collar workers, 875 blue collar workers, and 102 professional research workers in a large electronic company. Fourteen job stressors and six job stress variables were measured. There were significant differences in most of job stressors and job stress variables among the three groups. Inter-department conflict and participation on decision making scores were higher in the white collar group than in the two other groups. Leader relation, job insecurity, and environment problem scores were the highest in the blue collar group. Scores of role ambiguity, role overload, role underload, promotion problem, wage problem, and work-family conflict were the highest in the professional research group. Results of stepwise multiple regression analyses showed that peer relation, environment problem, and work-family conflict were significant in explaining the six job stress variables for the white collar group. For the blue collar group, peer relation, work-family conflict, work-aptitude incongruity, and participation on decision making were significant in explaining the six job stress variables. For the professional research group, only role overload was significant in explaining three of the six job stress variables. Finally, implications and limitations of this study were discussed