A flow control device includes an opening part through which an upstream side of a fluid flow passage is in communication with a downstream side of the fluid flow passage. A valve element closes the opening part and includes a large flow rate controlling valve element capable of adjusting an opening degree of the opening part, a sealing member provided with a valve hole having an open area smaller than the opening part and formed to be capable of being brought into tight contact with a peripheral wall part of the opening part and a small flow rate controlling valve element capable of adjusting an opening degree of the valve hole. A valve drive device rotates to drive the valve element in a closed direction for closing the opening part or in an opened direction for opening the opening part.