Most industrial accidents occur when the workers' unsafe behavior and the unsafe situation of workplace take place at the same time. Although human's unsafe behavior is indispensable to work field, the evaluation scheme to detect the causes for the accident resulted from human's unsafe behavior and counterplan should be prepared to prevent and reduce accident. To do this, we first classify the specific background factors in terms of human inner factor and environment factor and then develop the AHP (Analytic Hierarchy Process) model to analyze the background factors that affect the worker's unsafe behavior. We also develop a checklist to be able to evaluate the occurrence possibility of individual worker's unsafe behavior.