In order to prevent the agglomeration and improve the dispersion of ultrafine ceramic powders in liquid paraffin system etc. organic media, different kinds of polymer films were coated on the surface of ultrafine ZrO2 and SiC particles by low temperature plasma polymerization. The encapsulated powders were analyzed by TEM, TGA, and DRIFT. The results show that, the dispersion of plasma treated ZrO2 powders in the organic medium was better than that of untreated ZrO2 powders. The viscosity of liquid paraffin with same solid loading showed a significant difference between plasma treated and untreated ceramic powders.