An in-vehicle imaging device that adjusts a color gain of an image signal from an imaging unit loaded on a vehicle, comprising: a detection region setting unit which is adapted to set, for an image signal from the imaging unit, a detection region in accordance to a position and a shape of a predetermined object to be detected in an imaging screen a color signal determination unit which is adapted to set a specific color corresponding to the object to be detected and which is adapted to determine approximate color pixels from the pixels included in the detection region, wherein the approximate color pixels are pixels having color data corresponding to a color which is in the vicinity of the specific color; and a gain control unit which is adapted to average the color data of the approximate color pixels, to calculate a difference value between an average value of the color data of the approximate color pixels in the detection region and the color data of the specific color, and to adjust a color gain of the image signal on the basis of a calculated difference value between an average value of the color data of the approximate color pixels and color data of the specific color for reducing the difference value to zero; wherein the detection region setting unit selects one from a plurality of kinds of objects to be detected and sets the detection region corresponding to the selected one of the plurality of kinds of objects, and the color signal determination unit selects the specific color, the color corresponding to the selected one of the plurality of kinds of objects, wherein the in-vehicle imaging device further having a vehicle speed determination unit for determining a vehicle speed of the vehicle, wherein the detection region setting unit selects one from a plurality of kinds of objects to be detected in accordance with the vehicle speed and sets the detection region corresponding to the selected one of the plurality of kinds of objects, and the color signal determination unit selects one of the plurality of kinds of objects to be detected in accordance with the vehicle speed and sets the specific color corresponding to this. a detection region setting unit which is adapted to set, for an image signal from the imaging unit, a detection region in accordance to a position and a shape of a predetermined object to be detected in an imaging screen a color signal determination unit which is adapted to set a specific color corresponding to the object to be detected and which is adapted to determine approximate color pixels from the pixels included in the detection region, wherein the approximate color pixels are pixels having color data corresponding to a color which is in the vicinity of the specific color; and a gain control unit which is adapted to average the color data of the approximate color pixels, to calculate a difference value between an average value of the color data of the approximate color pixels in the detection region and the color data of the specific color, and to adjust a color gain of the image signal on the basis of a calculated difference value between an average value of the color data of the approximate color pixels and color data of the specific color for reducing the difference value to zero; wherein the detection region setting unit selects one from a plurality of kinds of objects to be detected and sets the detection region corresponding to the selected one of the plurality of kinds of objects, and the color signal determination unit selects the specific color, the color corresponding to the selected one of the plurality of kinds of objects, having a vehicle speed determination unit for determining a vehicle speed of the vehicle, wherein the detection region setting unit selects one from a plurality of kinds of objects to be detected in accordance with the vehicle speed and sets the detection region corresponding to the selected one of the plurality of kinds of objects, and the color signal determination unit selects one of the plurality of kinds of objects to be detected in accordance with the vehicle speed and sets the specific color corresponding to this.