The paper describes a study of the effect of salts of natural naphthenic acids on the rooting of young sunflower cuttings and latteral branching of interspecies sunflower hybrids. Naphthenic acids were obtained by alkaline extraction from atmospheric gas oil fraction of Vojvodina crude oil “Velebit” and purified by column chromatography on alumina. Their sodium salts in concen trations of 1×10-7 mol/dm3 stimulated the formation of adventitious roots in sunflower cuttings even by a factor of 40 compared with control, the effect being also observed in lateral branches of interspecies sunflower hybrids. The obtained results suggest the possibility of using naphthenic acids as a means for rooting of plant cuttings.