Gangshang ultramafic rocks are mainly composed of garnet peridotites and dunite, which contain olivine, chrome-spinel, diopside, endiopside, and/or garnet, orthopyroxene, amphibole and phlogopite. Chrome-spinels in Gangshang ultramafic rocks are varied in composition, with Cr#[100Cr/(Cr+Al)] ranging from 51 to 89, and its variation in composition is related to the four stages of the evolution of ultramafic rocks. Along with the evolution of ultramafic rocks, Cr# of chrome-spinels was increasing, Mg#[100Mg/(Mg+Fe2+)] of chrome-spinels was decreasing and the oxygen fugacity was increasing.In the course of amphibole facies and greenschist facies retrometamorphism, Cr, Mg and Al of chrome-spinels were reducing, but Fe was relatively increasing.