To investigate the factors influencing suicidal behavior of workers, self-report questionnaires (Korean Occupational Stress Scale, The Center for Epidemiologic Studies-Depression Scale, Alcohol Use Disorder Identification Test-Korea, Suicide Behaviors Questionnaire–Revised) were completed by 667 workers at 5 workplaces in C province in Korea from April to July 2016. The results of this study showed that the high and mid-high job stress groups had higher suicidal behavior ratings than the low group, and the high group had higher ratings than the mid-low group (F=7.50, p <.001). The depression group showed higher suicidal behavior than the normal group (t=249.55, p <.001), and the rating was higher for the alcohol use disorder group than the normal- and problem-drinking groups (F=9.94, p <.001). The regression model explained 30% of the variation in workers’ suicidal behaviors (F=18.86, p <.001), with significant variables such as depression (=0.41, p <.001), female (=0.13, p =.002), and job stress (=0.08, p =.042).