The invention provides a downhole explosion shell and a use method thereof, and belongs to the technical field of exploding. The downhole explosion shell comprises a semi-cylindrical first shell and a semi-cylindrical second shell, connecting buckles are correspondingly arranged on the first shell and the second shell, the first shell and the second shell are buckled, the first shell and the second shell are fixedly connected through buckles to form a cylindrical structure with the closed upper end and an opening in the bottom, the bottom of the cylindrical structure composed of the first shell and the second shell is fixedly connected with a shell bottom, the shell bottom is of a conical energy gathering hole structure, and a wire hole and an air guide pipe hole are formed in the connecting position of the upper end of the first shell and the upper end of the second shell; the problem of water gun hole complex operation and storage space stringency are solved; a large amount of raised soil, poisonous gas and the like generated by explosive exploding can be greatly reduced.