This paper propose to make a Construction site safety management system using beacon indoor positioning technology. in this system, as using beacon, it can measure the position of worker who have smartphone or any device which have bluetooth function. there is two way to use technology of beacon, first one is distance technology which can alarm dangerous situation such as appoaching heavy equipment. second one is location positioning technology. it is the main technology which can measure the position of workers in real time. this system is based on low energy and accurate sensor, beacon, and have a low cost advantage. so it is expected to improve safety on the construction site.