PURPOSE: To provide a process for producing a hot-pressed sintered BN-AlN having uniform properties in the direction of pressing axis.

CONSTITUTION: A powdery mixture filled in a mold is hot-pressed and sintered by applying uniform pressure from above and below with the same pressing mechanisms. The displacements of two pressing mechanisms are controlled and synchronized to nearly equalize the baking shrinkages in both directions and obtain a hot-pressed sintered BN-AlN material having uniform properties in the pressing direction. The process enables the production of a large-sized sintered material having homogeneous texture to expand the application range of the material.