To provide a differential pressure transmitter which achieves further miniaturization of a body by decreasing a diameter of a pressure sensing diaphragm without causing problems such as hydrogen permeation and cracks.

A sensor chip 11 is embedded in a small packaging body 20. The sensor chip 11 has an excessive pressure protection function obtained by making recesses 11-2a, 11-3a of stopper members 11-2, 11-3 face one and the other surfaces of a sensor diaphragm 11-1. Barrier diaphragms (pressure sensing diaphragms) 21a, 21b are provided on a side face of the packaging body 20. All of the sensor chip 11, the barrier diaphragms 21a, 21b, and the packaging body 20 are made of a semiconductor material (e.g. SiN, sapphire, Si, SiC, quartz, and borosilicate glass, etc.).