To obtain a low-cost high-quality electrostatic capacity type pressure sensor element.

The invention comprises a substrate whose surface at least is insulated, an extraction electrode and a lower electrode individually formed apart in plane view on the surface, a support insulator formed to project from the lower electrode surface position around the lower electrode, and a diaphragm layer supported by a support insulator and arranged face to face with a specific gap to the lower electrode. The diaphragm itself is constituted of a conductive material, or an electrode layer is formed on the diaphragm layer, and an upper electrode is formed facing the lower electrode. The diaphragm layer itself or the upper electrode is electrically connected to the extraction electrode.