PURPOSE: To obtain reliability and durability by a construction wherein a transmitter is provided with a pressure detector having a remote diaphragm deflecting upon receipt of the pressure being measured, a diaphragm used to pressurize a deflecting member by transmitting the deflection of the remote diaphragm and so on.

CONSTITUTION: A body 21 is of single construction and a diaphragm 6 as a pressure receiving film is made to so function that it deflects in proportion to the deflection of a remote diaphragm 9. A plate 26 is attached by welding to the end of the body to which the diaphragm 6 has been attached, while a flange 28 is attached to the outside of the above plate 26. This flange 28 mechanically continuously holds the body 21 and a pressure detector 10. In the transmitter thus constructed, since the plate 28 is sandwiched between the body 21 and the flange 28 and since the plate 26 is attached to the body 21 through welding, the penetration of air and the lekage of an enclosed liquid are prevented. Thus reliability and durability become available.