Disclosed is a detection device for a drilling tunneling machine. The detection device for the drilling tunneling machine comprises a prospecting mechanism which is arranged inside a drill and multistage drill pipes, the drill is detachably connected with the drill pipes, and the drill pipes are connected with each another detachably; the prospecting mechanism comprises a radar antenna, a wirelesstransmitting module, an extension spring, a rotary seal, guide rods, a flexible shockproof shell, spring baffles, a compression spring, a baffle, an elastic collar, and a radar receiver. The detection device for the drilling tunneling machine is installed at the center of a drilling mechanism and can realize synchronous drilling and cutting by the telescopic movement of the radar antenna relativeto the drill pipes, and has the advantages of high detection accuracy, large detection range, good real-time performance, high reliability, low cost and the like.