Abstract: Gel polymer electrolyte was prepared by chemical cross-linking.The polyolefin membrane supported gel polymer electrolyte exhibited good electrochemical performance.Its room temperature conductivity was as high as 1.01×10^-3S•cm^-1, its lithium ion transference number was 0.41 and its electrochemical stability window on Al electrode exceeded 4.2 V. Polymer lithium ion battery was prepared by using the polyolefin membrane supported gel polymer electrolyte, and the influence of processing condition on the electrochemical performance of the polymer lithium ion battery was investigated.The processing conditions included: monomer addition amount and stacking methods of electrodes.The optimized polymer lithium ion battery had good electrochemical performance.Its discharge capacity at 1 C rate was 93.2% of the discharge capacity at 0.2 C rate. More than 80% of its discharge capacity retained after 100 times 1 C charge-discharge cycling.