This paper reviews the safety in Japanese coal mining industry and the influences of related technologies and social factors on the accidents are discussed. Although the various safety records have been improved significantly over the last fifty years, they still remain at unsatisfactory levels as compared to those of other industries. Aiming to reduce the accidents further, a new study project that focused on the human factors in mine accidents was started in 1989. The detailed results of the study are analyzed. The results show that there are still many technological problems and their solutions related to the accidents in the coal mining industry. Further efforts from both aspects of human factors and technologies must be made to reduce the injuries.