PURPOSE: To provide a semiconductor pressure sensor which can detect a plurality of differential pressures simultaneously at a constant accuracy through the use of a semiconductor pressure sensor chip.

CONSTITUTION: A semiconductor pressure sensor chip 11 having a plurality of differential pressure detecting parts 11b is disposed across a plurality of detection chambers 4A, 4B while hermetically sealing the partitioning part 3a between respective detection chambers 4A, 4B thus positioning respective differential pressure detecting parts 11a, 11b within respective detection chambers 4A, 4B. Since respective differential pressure detecting parts are provided for one semiconductor pressure sensor chip, positioning accuracy of each differential pressure detecting part can be equalized easily. When first and second objects G1, G2 to be detected are introduced into respective detection chambers 4A, 4B, differential pressure can be detected at a constant accuracy through respective differential pressure detecting parts of the semiconductor pressure sensor.