To provide a semiconductor pressure sensor where inspection accuracy is improved without causing increase in inspection processes and costs, and its junction surface inspection method.

The important point of a silicon wafer 2 is etched and a plurality of recessed parts 3 are provided for forming a plurality of diaphragms 4, and boron or the like is diffused to each diaphragm 4, thus forming a gauge resistor 5. A glass pedestal 7 is subjected to anode junction to the silicon wafer 2. A site other than sites that oppose the junction site of the silicon wafer 2 is metallized by metal using sputtering or the like to form a metal film 8 within a surface at the opposite side of a junction surface 13 of the silicon wafer 2 in the glass pedestal 7, and a site that opposes the junction site is subjected to mirror surface finishing to form a mirror surface 9. When inspecting the state of the junction surface 13, the junction surface 13 is directly observed through the mirror surface 9 from the side of the mirror surface 9 of the glass pedestal 7, thus inspecting the release of the junction surface 13 and the presence or absence of void.