Mixed-matrix membranes (MMMs) consisting of ethyl cellulose as continuous matrix and inorganic particle C-60 as dispersed phase were prepared for propylene/propane separation. The impact of the C-60 content on the separation properties of MMMs without and with ultraviolet cross-linking was investigated. The increment of decomposition temperature and single glass temperature of ethyl cellulose/C-60 MMMs indicates a strong interfacial interaction between polymer and fullerenes. After UV irradiation, the gas permeability coefficient of propylene and ideal separation factor of propylene/propane decreased, and new features appeared in scanning electron microscopy and atomic force microscopy images, testifying the photopolymerization reaction of C-60 at a depth near to the surface. C-60 could be acted as a possible replaced carrier for the separation of olefin/paraffin using membrane separation technology.