Abstract: in order to solve a small etection scpe and low accuracy problems existed in the pilot delection of the mine disaster sources with the present geological adar a nev geological radar antenna was provided to the utra deep detecion of the mine disaster souces.An separated plug type low frequency combined antennawas designed and developed and was related to three frequencies of 12.5.25. and 50.0 MHz.The resuts showed tht the anen with a plate-ype stoucture designcould enhance the directivity of the antena. The antenna impedance and the interace design of thelengthened bar could real e the enironmentimpedace machedin the feeding poit of the antenna system.coud enhance the antenmna bandwidth and could reduce the standing wave interference. The nev anen a was appied to thamine plot detection experinent.The results showied that the nevw antena could efiectvely detecthe location and dephof the geogicaldisaster source with distance over 30 m and a diameter over 3 m,could break the present 30 m detection depth limit and could have the max detection depth of 8o m.