A coefficient determination device determines, based on captured image data obtained by imaging a subject including one or more types of pigments, coefficients included in a function used to calculate a concentration of one desired pigment in a specific region of the subject. The coefficient determination device includes: a response calculation unit configured to calculate at least one of a first response mode indicating a relationship between a change in a component concentration of a pigment other than the desired one pigment and a change in each of the plurality of types of luminance values; and a second response mode indicating a relationship between a change in a shade intensity and a change in each of the plurality of types of luminance values; and a coefficient calculation unit configured to calculate the plurality of coefficients using at least either one of the first and second response modes.