PURPOSE: To manufacture a semiconductor pressure sensor which has high reliability at high temperatures in a short time by irradiating the semiconductor pressure sensor with a laser beam, etc., in a vacuum chamber, and thus boring a hollow shell and also blocking the hole by fusion.

CONSTITUTION: The semiconductor pressure sensor 1 is stored in the vacuum chamber 10, which is then evacuated to a specific degree of vacuum. Then, a specific part of the cap 5 of a sensor 1 is irradiated with a laser light beam 12 from a laser gun at the outside of the vacuum chamber through a window 11 to form a fine hole in the cap 5, and the space in the cap 5 is evacuated through the hole. When the space in the cap 5 attains to a specific degree of vacuum, the periphery of the hole is irradiated with laser light again and fused to block the hole, thereby sealing the space in the cap 5. Consequently, a sensor 1 need not be heated, so there is no possibility of deterioration and the high-temperature durable sensor is obtained in an extremely short time.