A method has been developed for the modification of carbon containing fillers for elastomers by deposition of soluble zinc ammoniate complex and subsequent decomposition of the complex to ZnO by heating. It has been found that the method ensures a simultaneous, favorable change of the initial porous texture of the filler (activated carbon) and formation of a supported ZnO phase containing hydroxyl groups. The resulting modified carbon filler exerts favorable effect on the mechanical properties of the vulcanizates as compared to those produced with unmodified carbon filler.