The necessity of installing underground personnel positioning system in coal mine was described, and its existing problems were researched to put forward a new type system, which could realize personnel attendance, downhole accurate positioning, downhole warning function with features of low cost, easy maintenance and strong expansion performance. It could effectively supervise underground personnel. Rescue personnel could quickly and accurately judge the orientation of person in distress according to location system when accident occurred, which improved rescue efficiency and provided valid protection for safety of underground personnel.