A flow control valve in which corrosion is less likely to occur in the vicinity of a radial step portion in a gas passage of a housing and a method for manufacturing the same are provided. A flow control valve includes: a housing formed with a gas passage including a first cylinder member accommodating portion, a second cylinder member accommodating portion, and a radial step portion; a first cylinder member accommodated in the first cylinder member accommodating portion; a second cylinder member accommodated in the second cylinder member accommodating portion; and a valve body that is rotatably arranged inside the first cylinder member and the second cylinder member in the radial direction. The housing is formed of cast iron. At least surfaces of the first cylinder member and the second cylinder member are formed of a highly corrosion resistant material. At least one of a first axial end surface and a second axial end surface includes an opposing portion that opposes the radial step portion in the axial direction. A gas seal structure is arranged between the opposing portion and the radial step portion.