To acquire accurate information on object colors by uniform processing, regardless of the magnitude of the intensity of the external light.

This object color measuring method is for carrying out measuring of object colors of a photographic subject 10 that is illuminated by external light, and uses rays of illumination light of white (W), made by combining the individual monochromatic colors of red (R) and green (G) and blue (B), magenta (M) made by combining the individual monochromatic colors of R and B, cyan (C) made by combining the individual monochromatic colors of B and G, and yellow (Y), made by combining the individual monochromatic colors of G and R. The method includes: a stage for measuring information on each color of the photographic subject 10 irradiated with both the external light and illumination light of W, both the external light and illumination light of M, both the external light and illumination light of C, and both the external light and illumination light of Y; and a stege for calculating the information on each color of the photographic subject, in a state of being irradiated with illumination light of R, illumination light of G, and illumination light of B.