Surface modification of precipitated calcium carbonate particles in a planetary ball mill using different dispersants such as stearic acid, oleic acid, palmitic acid, salicylic acid, oleyl amine, DDSA (dodecenyl succinic anhydride), ODSA (octadecenyl succinic anhydride), TPSA (tetra propenyl succinic anhydride) as modification agent was done in order to find out the potential of dispersant in surface modification and for making dispersion in hydrocarbon oil was investigated. Different dispersants were ball milled keeping all the parameters for processing (milling) like milling time, ball ratios, sample dosage and milling constant. The physical properties of the hydrophobically modified calcium carbonate were measured; the particle size and morphology of the resulting samples were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The surface coating thickness was also estimated by geometric calculation using results of TEM and TGA considering the formation of core shell structure. (C) 2012 Elsevier B.V. All rights reserved.