An electrostatic capacitance type pressure sensor comprising: a diaphragm having a center part displacing in accordance with a pressure of a medium to be measured; a sensor pedestal that is adapted to secure a peripheral edge part of the diaphragm and to form a reference vacuum chamber in cooperation with the diaphragm; a cover plate bonded to the peripheral edge part of the diaphragm on the opposite side from the sensor pedestal, the cover plate being adapted to form a pressure introduction chamber in cooperation with the diaphragm; a fixed electrode formed on a surface of the sensor pedestal on the side of the reference vacuum chamber; and a movable electrode formed on a surface of the diaphragm on the side of the reference vacuum chamber so as to face the fixed electrode, wherein the diaphragm has a step part between a peripheral edge part and a center part on the side of the pressure introduction chamber, and is divided into a region on the center part side and a region on the peripheral edge side at the step part as a boundary, a thickness of the region on the center part side being formed thinner than that of the region on the peripheral edge side, characterised in that: the cover plate has a plurality of pressure introducing holes adapted to introduce the medium to be measured into the pressure introduction chamber from a direction crossing the surface of the diaphragm, a center of each opening of the plurality of pressure introducing holes facing the pressure introduction chamber being arranged so as to be within a range of ±15% of the radius of the diaphragm from the step part of the diaphragm in the direction parallel to the surface of the diaphragm. a diaphragm having a center part displacing in accordance with a pressure of a medium to be measured; a sensor pedestal that is adapted to secure a peripheral edge part of the diaphragm and to form a reference vacuum chamber in cooperation with the diaphragm; a cover plate bonded to the peripheral edge part of the diaphragm on the opposite side from the sensor pedestal, the cover plate being adapted to form a pressure introduction chamber in cooperation with the diaphragm; a fixed electrode formed on a surface of the sensor pedestal on the side of the reference vacuum chamber; and a movable electrode formed on a surface of the diaphragm on the side of the reference vacuum chamber so as to face the fixed electrode, wherein the diaphragm has a step part between a peripheral edge part and a center part on the side of the pressure introduction chamber, and is divided into a region on the center part side and a region on the peripheral edge side at the step part as a boundary, a thickness of the region on the center part side being formed thinner than that of the region on the peripheral edge side, characterised in that: the cover plate has a plurality of pressure introducing holes adapted to introduce the medium to be measured into the pressure introduction chamber from a direction crossing the surface of the diaphragm, a center of each opening of the plurality of pressure introducing holes facing the pressure introduction chamber being arranged so as to be within a range of ±15% of the radius of the diaphragm from the step part of the diaphragm in the direction parallel to the surface of the diaphragm.