A novel method for incorporation of palladium nanoparticles into a porous hypercrosslinked polystyrene matrix has been developed. The composite obtained by reduction of [Pd(pi-allyl)Cl](2) with hydrogen in supercritical CO2 shows high catalytic activity in the hydrogenation of benzene and can be used twelve (12) times in a row without any decrease in conversion rate. The catalyst is also suitable for quantitative hydrogenation of toluene, tetralin and phenol. The obtained catalytic system is compared with the palladium composite synthesized by a conventional method based on hypercrosslinked polystyrene.