The related design of electrode with large area uniform electric field and the experimental results are introduced in this paper. The distribution of electric field is uniform between two electrodes with boundless parallel slab, but the problem is the uniform design of electric field in the condition of limited size of electrode. Therefore the theoretical and engineering computations are crucial to solve this problem. According the practical condition of TEA CO2 laser, Chang theory is chose as the reference of design. The experimental results of electrode discharge after the design show that the uniform glow discharge in large area is realized between two main electrodes. with 55mm electrode width and flatness part 40mm section. The TEA CO2 laser is able to continuously work for 10minutes in the condition of high repetition rate 500Hz.