The utility model provides a gas density real -time monitoring system of different degree of depth of driling, including gas density collection host computer, a collection appearance and a plurality of consistency transmitter, this gas density collection host computer passes through the cable to be connected with consistency transmitter, is connected with the collection appearance through wirelessa gas density real -time supervision module, each consistency transmitter detects gas density information and generates the signal of telecommunication in all being fixed in a protecting tube, gathers host computer with this electricity signal transmission for gas density through the cable, this gathers the appearance through wireless and computer link. This system can realize the gas density real -time supervision to the different degree of depth of driling, acquires gas density information and concetration change characteristic in real time, in time sends the early warning of gas high concentration, avoids the emergence of gas accident, improves borehole operation's security. The simple structure of this system, intelligent degree is high, convenient operation.