Objective: The goal of current study was to investigate the main reasons of unreported accidents in a view point of system, person, and working environment.BRBRBackground: Various accidents could happen anytime and anywhere of the industrial sites. Regardless of the accident severity and type, industry have been emphasized the importance of accident reporting to prevent a severe accident in future. Despite of the effort to increase the accident report, numerous numbers of near-misses and minor accidents were not reported in various reasons.BRBRMethod: The current study was conducted with a questionnaire, consisted of three main question and 22 sub-questions asking about the reason of the unreported accidents. Total 763 workers at a chemical company in Republic of Korea answered the questionnaire.BRBRResults: In both 2016 and 2018, more than 80% of workers agreed the sentence that the accident must be reported. Regardless of the individual