The modification of Shenfu coals by a microwave treatment carried out under a hydrogen or a methane atmosphere,and the subsequent maceral separation by flotation,are described in this paper,The surface contact angle and the Zeta potential of the coal macerals were measured both with and without the treatment.The results show that the surface wettability ofSFF (Shenfu Fusain) and SFV (Shenfu Vitrain) can be changed by the microwave treatment.An increase in the difference in surface wettability of SFF and SFV causes in a subsequent increase in the enrichment of inertinite and vitrinite.The results of the Zeta potential measurements show that the surface potentials of SFF and SFV are also changed by the treatment.