Polymeric biocompatible microparticles based on a copolymer of lactic and glycolic acids with the inclusion of magnetic nanoparticles, perfluorodecalin and radachlorin as an active substance were obtained by the method of multiple emulsion. It has been shown that the obtained microparticles have a sufficient inclusion of radachlorin to generate singlet oxygen and manifest a photocytotoxic effect when exposed to light radiation used in photodynamic therapy.