To provide a high-temperature and high-pressure gas producing device having simple small-volume construction with high safety and high energy usability.

The high-temperature and high-pressure gas producing device comprises a combustion furnace 10, a fuel transport mechanism 20, an ignition mechanism 40, and an air introduction mechanism 30. The combustion furnace 10 has a combustion chamber 11 formed in the furnace body. An ash discharge port 12 is provided in the lower part of the furnace body and a high-temperature and high-pressure gas discharge pipe 13 is provided in the upper part of the furnace body. The fuel transport mechanism 20 transports solid fuel such as coal or chacoal into the combustion furnace 10. The air introduction mechanism 30 introduces air into the combustion chamber 11 of the combustion furnace 10. The ignition mechanism 40 performs initial ignition of the solid fuel in the combustion furnace 10. The produced high-temperature and high-pressure gas is discharged form the high-temperature and high-pressure gas discharge pipe 13 in the upper part of the combustion furnace 10 to drive a machine device such as a gas turbine 50. Additionally, the high-temperature and high-pressure gas is used as motive force for operating equipment such as a vehicle 60A, a pump motor 60B or an AC generator 60C.