After clarifying the spectrochemical features of biliverdin and bilirubin, absorption spectral analyses of their oxidative decompositions, absorption spectral analyses of their oxidative decompositions, following chromatographic fractions, were performed, and the following results were obtained. 1. As biliverdin was unstable chemically, accessory products were easily formed by washing bilirubin with water. 2. Choletelin, propentdyopent urochron etc, were proved, following the oxidation of biliverdin, 3. A blue colored chemically unstable substance was present after the oxidation of bilirubin, at wihch time the formations of biliverdin, propentdyopent and urochrom were proved in the absorption spectra.