OBJECTIVE: This study investigated the driving habits of taxi drivers, in order to examine the characteristics of human factors causing traffic accidents and unsafe driving behavior and to determine any relevancy among them. METHOD: Taxi drivers (N=335) answered a questionnaire investigating various measures of human factors, unsafe driving behaviors, and number of traffic accident experiences in the previous year. In factor analysis, the characteristics of human factors were classified into 5 common factors: job, mental health, age, health habit and sleep factor. A contextual mediated model was proposed to distinguish the distal (5 common factors) and proximal (unsafe driving behaviors) factors in predicting traffic accident involvement by hierarchical multiple regression. RESULT: In hierarchical multiple regression, job factor(beta: 0.122), sleep factor (beta: 0.114) and unsafe driving behaviors (beta: 0.018) yielded a direct effect on the rate of traffic accidents. Mental health factor beta: 6.429), job factor (beta: 1.319) and health habit factor(beta: 1.177) yielded a indirect effect on the rate of traffic accidents by unsafe driving behaviors. CONCLUSION: Various human factors co-related by the unique characteristics that exist in the taxi service industry have significant effects on the rate of traffic accidents mediated by unsafe driving behaviors. Therefore a proper countermeasure against these factors should be established in order to effectively reduce the rate of taxi accidents.