The application of Curie-point pyrolysis—gas chromatography—mass spectrometry to the differentiation of melanosomes isolated from the retinal pigment epithelium, ciliary body and iris of cattle eyes, with special attention to the preparation and the characterization of their melanin part, was investigated. Computer data analysis and evaluation of the pyrograms obtained was used to display variations between the pyrograms of melanosomes and their components represented by sets of peak heights for comparative studies. The mechanisms of formation of the pyrolytic products and the usefulness of the proposed procedure based on pattern recognition in view of biochemical processes in melanosomes are discussed.