High-pressure gas quenching is the heat treatment technology which quenches the works by use of high-pressure and high-speed flow gas. FLUENT software is used to simulate the process of gas-solid coupling flow and heat transfer in the nozzle-type vacuum high-pressure gas quenching furnace. The hot wire anemometer is used to measure the inlet velocities of nozzles, which provides the boundary conditions for computer simulation. By the computer simulation, the gas flow fields, work temperature fields and work cooling curves are attained. The results show that the big eddy current occurs at the corner of the furnace and the cooling rate of the work is slow there. Contrasting the simulating result of work cooling rate at the center of furnace with the actual measured one by the thermocouple, we find when work is cooled to the temperature of 430K, the simulating result is faster than the actual one about 50 seconds. The simulating results basically correspond with the actual trend of the gas quenching.