Abstract: Combining field detection with physical simulation, it studied the metal interference from drilling jum? bo, steel arch, etc on the detection results by transient electromagnetic method. The results show that: 1) the metallic body behind the working face has some interference on the detection results by transient electromagnetic method, of which the interference coefficient will decrease with an increase of the distance between the metallic body and the detection line, indicating that the results from physical simulation agree well with the ones from field test; 2) the interference coefficient has something to do with the signal strength of detection target, i.e. with a constant location of the metallic body, its interference coefficient will decrease with an increase of the low-resistant anomalous value ahead of working face; 3) to reduce the metal interference during the advance geological forecast, the drilling jumbo shall be at least 30 m away from the working face and the detection line shall be at least 1 m away from the sidewall.