A flow control valve has a housing, a valve element, a drive member, a drive-member thread, a valve thread, a drive-member detent part, and a valve detent part. A direction where the valve element gets close to a valve seat is a positive direction and an opposite is a negative direction. A first value is a value indicating a distance from an end of the drive-member detent part in the positive direction to an end of the drive-member thread in the positive direction, and a second value is a value indicating a distance from an end of the valve detent part in the negative direction to an end of the valve thread in the negative direction. The second value is larger than the first value.