A flow control device is capable of performing accurate flow control over a wide range of temperatures by using a housing made of resin with superior chemical resistance. The flow control device includes: a housing made of resin; a diaphragm which is supported in the housing so as to split the housing into a gas chamber side to which gas is introduced and a fluid chamber side through which fluid passes, and is activated by the differential pressure between the gas chamber side and the fluid chamber side; and a valve body which operates in integration with the diaphragm to regulate the flow of the fluid introduced into the fluid chamber side. The gas chamber side includes a holding member which holds the diaphragm between itself and an opposing surface of the fluid chamber side opposite to the diaphragm, the holding member being screwed to the inner peripheral wall of the gas chamber side through a screw part.