Ethylene-propylene-diene monomer (EPDM) is obtained by copolymerizing ethylene and propylene monomer in a solution under the Ziegler-Natta catalyst and introducing a small amount of third, non-conjugated diene monomer. All the third monomer conjugated dienes include 1,4-hexadiene (1,4-HD), dicyclopentadiene (DCPD) and ethylidene norbornene (ENB). The products containing EPDM features excellent weatherability, good resistance to ozone, aging and chronic chemicals, good flexibility under low temperature and low conductivity. EPDM can be used for extruded products, rubber strips for buildings and automobiles, rubber hoses, open-cell and closed-cell sponge rubber, roller sleeves and insulation materials for low-voltage cables. EPDM has excellent foaming capability, elasticity and flexibility, making itself widely used for purposes such as sealing, shock absorption and resistance to coldness, chemicals and wear.