A throttle valve for an internal combustion engine; the throttle valve comprises: a valve body; a tubular feeding duct, which is defined in the valve body and through which the air taken in by the internal combustion engine flows; and a throttle plate, which is arranged inside the feeding duct and is splined to a shaft, which is mounted in a rotatory manner, so as to rotate around a rotation axis between a maximum opening position and a closing position to open and close the feeding duct; wherein the valve body comprises an annular-shaped inner body, which is made of a first material, defines a central portion of the feeding duct, and is arranged in correspondence to the shaft of the throttle plate, so that, in the closing position to close the feeding duct, the outer edge of the throttle plate is close to an inner surface of the inner body; wherein the valve body comprises an outer body, which is made of a second material that is different from the first material, encompasses the inner body leaving the inner surface of the inner body visible, and makes up the remaining part of the feeding duct on the opposite sides of the inner body; and wherein the inner body has two axially opposite annular walls, each of which surrounds the feeding duct; each annular wall of the inner body is provided with at least one groove, which is obtained in the middle of the annular wall; the throttle valve is characterized in that: each groove is delimited, on one side, by an inner edge with a smaller diameter and, on the other side, by an outer edge with a larger diameter; and in each groove, the inner edge has a height that, when measured in an axial direction, is smaller than the height of the outer body. a valve body; a tubular feeding duct, which is defined in the valve body and through which the air taken in by the internal combustion engine flows; and a throttle plate, which is arranged inside the feeding duct and is splined to a shaft, which is mounted in a rotatory manner, so as to rotate around a rotation axis between a maximum opening position and a closing position to open and close the feeding duct; wherein the valve body comprises an annular-shaped inner body, which is made of a first material, defines a central portion of the feeding duct, and is arranged in correspondence to the shaft of the throttle plate, so that, in the closing position to close the feeding duct, the outer edge of the throttle plate is close to an inner surface of the inner body; wherein the valve body comprises an outer body, which is made of a second material that is different from the first material, encompasses the inner body leaving the inner surface of the inner body visible, and makes up the remaining part of the feeding duct on the opposite sides of the inner body; and wherein the inner body has two axially opposite annular walls, each of which surrounds the feeding duct; each annular wall of the inner body is provided with at least one groove, which is obtained in the middle of the annular wall; the throttle valve is characterized in that: each groove is delimited, on one side, by an inner edge with a smaller diameter and, on the other side, by an outer edge with a larger diameter; and in each groove, the inner edge has a height that, when measured in an axial direction, is smaller than the height of the outer body. each groove is delimited, on one side, by an inner edge with a smaller diameter and, on the other side, by an outer edge with a larger diameter; and in each groove, the inner edge has a height that, when measured in an axial direction, is smaller than the height of the outer body.