The invention discloses a polymer composite separator for a lead acid storage battery, and the polymer composite separator comprises the following raw materials by weight: 50-70 parts of polypropylene, 40-60 parts of polyethylene, 5-12 parts of silica, 15-25 parts of maleic anhydride, 1-3 parts of an initiator, 4-8 parts of an additive, 8-15 parts of glass fiber, 10-20 parts of an impregnating compound, 0.8-2 parts of a coupling agent, 1-3 parts of an antioxidant, 2-5 parts of a rare earth material, 10-16 parts of a hydrochloric acid solution and 16-24 parts of a non-ionic surfactant. The polymer composite separator for the lead acid storage battery has the advantages of super-high strength, toughness and permeability resistance, large flexural coefficient, good heat resistance and oxidation resistance, simple preparation method, no high cost equipment investment, low production cost and suitability for industrial production, the polymer composite separator for the lead acid storage battery is used in the lead-acid battery for effectively reducing the short-circuit problem caused by the separator, prolongs the service life of the lead acid storage battery, and widens the application prospect.