The present invention is vacuum high pressure pulse discharge catalyzed chemical heat treatment apparatus and method. The apparatus consists of furnace seat, catalytic discharge electrode on the furnace, catalytic discharge electrode, pulse power supply, furnace gas circulating system, heat isolating layer structure, inside AC heater, etc. The method includes setting the workpiece inside furnace, heating with the inside AC heater to nitriding temperature, applying pulse voltage of 0-8000 V between the catalytic discharge electrode on the furnace and the catalytic discharge electrode, ionizing the nitrogen containing gas inside the furnace and of pressure 100-50000 Pa to discharge intensively to generate active nitrogen atoms permeating into the workpiece at high speed, and circulating nitriding gas for passing by the workpiece homogeneously. The present invention has the advantages of fast nitriding, high heat efficiency, no oxidation of the workpiece, etc.