Abstract: The invention relates to the field of producing polymer sorbents having magnetic properties, and can be used for removing petroleum products from a water surface. A magnetic porous sorbent for removing thin petroleum films from a water surface is proposed, said sorbent being produced on the basis of industrial synthetic divinyl rubber, as a result of the modification thereof by an oxidative chlorophosphorylation reaction with subsequent immobilization of magnetite FeO nanoparticles; and a method for producing a magnetic material is proposed, said method comprising the formation of FeO nanoparticles by an ion deposition method directly within a porous polymer matrix. The sorbent has a good sorption capacity in relation to thin petroleum films.