In the present work we prepared tris(alkylxanthato)chromium(III) and intended to study the photochemistry of these complexes in dimethyl sulfoxide. These complexes might be useful in many applications. Moreover, metal chelate with metals at high oxidation state is active in the enhancement of photodegradation of plastic and therefore, might serve as photocatalyst to treat the plastic waste pollution problem. The effect of number of methyl group in these complexes has been also studied. This work also deals with the photochemical reaction and determination of quantum yields and reactivity...