To provide an electrostatic capacity type pressure.difference pressure transmitter having a structure capable of reducing the asymmetry of temp. characteristics without complicating a sensor structure and capable of keeping resolving power in low cost.

A pressure sensor 10 is composed of a threelayered structure of glass block 2a-Si diaphragm 1-glass block 2b and the glass block 2b on the single side (low pressure side) of the pressure sensor 10 and a flange 11 are alitightly bonded through an insulating component 3b and an insulating component 3a is provided in the glass block 2a on the other side (high pressure side) of the pressure sensor 10 in the positional relation corresponding to the insulating component 3b of the glass block 2b on the single side to make the temp. characteristics on both sides of the pressure sensor 10 equivalently symmetric.