A buffer combining polymeric elastic components and metal friction components comprises a shell, one set of the polymeric elastic components, one set of metal spacers, a wedge block installation cylinder, a set of wedge block bodies, a pressing block, a mandrel, a nut and a thread connection looseness preventing piece. The elastic components, the metal spacers, the wedge block installation cylinder, the wedge block bodies and the pressing block are fixedly connected with the shell through the nut and the thread connection looseness preventing piece which are arranged at the end of the mandrel. The buffer has the beneficial effects that compared with an existing elastic body buffer, the buffer is higher in energy absorption rate; the working environment of the elastic components and the metal spacers is superior to that of elastic components and metal spacers of the existing elastic body buffer; and the buffer is simple in structure, small in part number, low in manufacturing cost, easy to use, maintain and operate and high in reliability.