PURPOSE: To enhance a fixing strength and improve a temperature characteristic by giving a state where the part surrounding a screen is buried in a case.

CONSTITUTION: Brim 9 is provided in the part inner a little from the aperture edge part of cylindrical case 8 which stores vibration part 7 of an ultrasonic ceramic microphone. Mesh-shaped metallic screen 10 is provided which is inserted from the aperture edge part of case 8 into case 8. Next, the aperture edge part of case 8 is bent inside, and screen 10 is held between brim 9 and the bent part. When waveform convexes and concaves are given to the upper face of brim 9 and the case inside wall face near the aperture edge part, the screen can be compressed under a state where the screen is fitted to these convexes and concaves, so that a holding strength can be enhanced. Further, since no adhesive is used, a temperature characteristic can be improved.