The invention relates to the technical field of thermal treatment molds, in particular to a press quenching mold for a locomotive traction gear ring. The press quenching mold comprises an upper mold body and a lower mold body. The upper mold body comprises a web pressing mold body and an end face pressing mold body. The lower mold body comprises an expanding core, a web supporting table and an end face supporting table. The web supporting table and the web pressing mold body are used for clamping a web of the locomotive traction gear ring; the end face supporting table and the end face pressing mold body are used for clamping the end face of the locomotive traction gear ring; the expanding core comprises a stand column, a circular cone stand, an expander and an expander supporting table; the stand column and the expander supporting table are fixed to a machine tool working table; the circular cone stand is arranged on the stand column in a sleeved mode and can move up and down along the stand column; the expander is arranged around the periphery of the circular cone stand, the bottom of the expander makes contact with the expander supporting table and can perform radial movement on the expander supporting table; the inner inclined surface of the expander is attached to the outer conical surface of the circular cone stand. The press quenching mold for the locomotive traction gear ring is compact in structure and ingenious in design; during carburizing and quenching, the requirement of products for the hardness can be met and deformation of the gear ring due to carburizing and quenching can be effectively controlled; therefore, the qualified rate of the products is increased.