Gear transmission box capable of preventing oil leakage

The invention relates to the technical field of gear transmission boxes, and discloses an oil leakage prevention gear transmission box which comprises a main body shell, a gear assembly is installed in the main body shell, a shaft inlet pipe is installed on a flange in the middle of the left end of the main body shell and used for being connected with an input shaft rod, and an output shaft rod is in vertical transmission with the shaft inlet pipe. The input shaft rod and the output shaft rod are in meshing transmission on the inner side of the main body shell through the bevel gear. According to the gear transmission box capable of preventing oil leakage, after helium on the inner side of the core pad is heated to expand, the rubber ring part can annularly collide, wrap and cling to the bolt by utilizing the guide of the bevel part to the expansion deformation of the core pad, so that the thread part of the bolt is further sealed, and the problem that lubricating oil leaks from the connecting part is effecti