Poly(acrylonitrile-vinyl acetate) (P(AN-VAc)) was synthesized by emulsion polymerization with different mole ratios of acrylonitrile (AN) to vinyl acetate (VAc). P(AN-VAc) membrane was prepared with phase inversion method and was activated by poly(methyl methacrylate) (PMMA) to prepare a new type of gel polymer electrolyte matrix, P(AN-VAc)/PMMA. The performances of the synthesized copolymer and prepared polymer matrixes were characterized with FTIR, TGA, SEM, electrochemical and mechanical test. Compared with P(AN-VAc), P(AN-VAc)/PMMA is better as the matrix for gel polymer electrolyte for lithium ion battery use. P(AN-VAc)/PMMA has higher mechanical strength than P(AN-VAc) and the gel polymer electrolyte based on P(AN-VAc)/PMMA has higher electrochemical and chemical stability and ionic conductivity.