Existing research on work ethic appears to have two major limitations. First, in most studies, the concept of work ethic has been equated with the historically and culturally limited Protestant work ethic, resulting in a lack of conceptual generality. Second, in empirical research, either the variables examined have been limited, or even when multiple variables were considered, the analysis remained at an exploratory level of identifying relationships without theoretical review or a systematic framework. The purposes of this study are (1) to establish a generalizable concept of work ethic, and (2) to present a framework for the determinants of work ethic and to empirically verify it. This study demonstrated that work ethic comprises the value of work, work centrality, and work performance attitudes, and developed a corresponding questionnaire that served as the dependent variable in the empirical study. Antecedent variables of work ethic included (1) personality variables such as locus of control, growth need strength, and Type A personality; (2) socialization toward work at home and in the workplace; (3) job-related variables such as job characteristics and job self-efficacy; and (4) demographic characteristics such as age, gender, social class, and religion. A survey was administered to 600 workers from four companies for the empirical study. Regression analysis results showed that work ethic was more proactive when (1) internal locus of control, higher-order need strength, and Type A personality were stronger; (2) socialization toward work at home and in the workplace was greater; (3) job characteristics were more enriched and job self-efficacy was higher; and (4) workers were older. An unexpected finding was that women exhibited a more proactive work ethic than men, and workers from higher-income households and those with more years of education showed a less proactive work ethic. The conclusion section discusses the theoretical and practical implications of these findings, as well as the study's limitations and directions for future research.