Abstract: Packer rubber element is the critical component of water swelling packer.The packing effect of packer is dependent on the property of water-swelling rubber.domestic in-depth research on rubber of this kind of packer and its synthetic materials is rare.Water absorbent resin is synthesized from sodium acrylate and acrylamide copolymerization in order to raise its resistance to salt.Factors which affect the water-absorption of resin are studied,and it is found that the water absorption of resin can be adjusted through changing monomer mixture rate and concentration.Nitrile butadiene rubber and water-absorbent resin are blended to make water swelling rubber.The influences of concentration and pH value of saline solution on the rubber swelling ability are studied.Tensile strength of the rubber was tested,too.Results of tests indicate that swelling ability of rubber depends on all factors mentioned above.Tensile strength of water swelling rubber made by us is very good.Finally,laboratory tests of isolation ability of the water swelling packer made with our synthesized rubber were conducted,the pressure bearing capacity up to 14 MPa,it can meet the requirement of shallow well opertation.