PURPOSE: To lessen a sensor package in size by a method wherein a first package member is equipped with a sensor element mounting pad and leads, and a second package member is joined to the sensor element mounting pad of the first package member.

CONSTITUTION: A sensor element composed of a glass pad 2 and a semiconductor chip 1 is mounted on a lower package member 3, and the semiconductor chip 1 is connected to a lead 6 with a bonding wire 5. Thereafter, an upper package member 4 is joined onto the lower package member 3, and a peripheral O ring 7 is provided to the periphery of the upper package member 4. As a wire bonding operation is executed while the upper package member 4 is kept in an unjoined state, it is not required that, an opening 8 provided to the upper package member 4 is set large in area. Therefore, the O ring 7 can be provided overlapping a wire bonding region in a top view, and a sensor package of this constitution can be lessened in size.