Tunnel exploration drilling sampling device

The utility model relates to a sampling device for tunnel exploration drilling. An existing drilling sampling device has the problems that a pipeline needs to be disassembled and assembled frequently, and the sealing performance of the pipeline is reduced. The device comprises a sampling barrel arranged in a drill rod, wherein the sampling barrel comprises a containing barrel and a fixing barrel which are arranged up and down and movably connected; a containing groove is formed in the inner wall of the containing cylinder, a connecting assembly connected with the drill rod is arranged in the containing groove, and the connecting assembly comprises a locking block, a reset spring, a mounting base, a gear and a rack. Horizontal positioning holes are formed in the groove bottom of the containing groove and the inner wall of the corresponding drill rod, the hole bottom of each positioning hole is an inclined face, one end of each locking block is an inclined face and is inserted into the corresponding positioning