The macro-initiator for atom transfer radical polymerization (ATRP), bromoacetyl modified polyaniline (BrA-PANI) with a bromoacetyl group content of 0.27 m mol/g, was successfully prepared by the bromoacetylation of the amine groups of the undoped PANI with bromoacetylbromide. Then the poly(methyl methacrylate) (PMMA) brushes were grafted from the BrA-PANI surface via a surface-initiated atom transfer radical polymerization (SI-ATRP) of MMA with the catalysts of 1,10-phenanthroline and Cu(I)Br. The percentage of grafting (PG%) was found to increase linearly with the increasing of the polymerizing time and that of 27.18% was achieved after the SI-ATRP in toluene solution at 80 degrees C for 6 h. The product, the shell-core poly(methyl methacrylate)-polyaniline (PMMA-PANI) powders were also characterized by FT-IR, XPS and SEM.