Provided is an image detection device including a light-emitting unit that emits light toward an image holding member, a first light-receiving unit that is disposed at a position where specular reflected light of the light emitted toward the image holding member is received, a second light-receiving unit that is disposed at a position where diffuse reflected light of the light emitted toward the image holding member is received, a light-emission control unit that controls an intensity of the light emitted by the light-emitting unit, and a reference member that is disposed at a position through which light having an intensity that is less than an intensity detectable by the second light-receiving unit passes in a case of the first intensity and through which light having an intensity that is equal to or higher than the intensity detectable by the second light-receiving unit passes in a case of the second intensity.