PURPOSE: To provide a hot press apparatus which enables using of a compact mold with a less thickness to accomplish thermal and pressure molding of a large sample at a high accuracy withstanding a high pressurizing force.

CONSTITUTION: A sleeve 12 formed by being divided axially is arranged in a cylindrical mold 11 with a thickness thereof varied gradually in the axial direction thereof. In addition, punches 13 and 14 operated by a cylinder mechanism are arranged at both end parts in the sleeve 12. The cylinder mechanism of the hot press apparatus which performs a pressure molding of a sample M filled in the sleeve 12 with punches 13 and 14 from both sides thereof heating the sample M is provided with a control mechanism to operate the punches 13 and 14 so as to accomplish the pressure molding of the sample M filled at the center position in the axial direction of the mold 11 moving it to the larger thickness side of the mold 11.