NOVELTY - Nickel oxide powder, yttria-stabilized zirconia powder and pore-making agent are mixed, pressed and sintered, to obtain electrolyte film support. Yttria-stabilized zirconia (YSZ) powder electrolyte film (a) is coated on support, to form YSZ electrolyte film (a) support. YSZ electrolyte film (b) is coated on surface of YSZ electrode layer (a), to form YSZ electrolyte layer (b) on surface of support. A lanthanum-strontium-manganese-YSZ pulp is coated to electrolyte of nickel oxide-YSZ hydrogen support/YSZ electrode sheet to obtain oxide electrolyzer cell electrode sheet.    USE - Electrolyte/oxygen electrode interface microstructure modifying method of solid oxide electrolyzer used for solid oxide fuel battery.    ADVANTAGE - The method efficiently improves hydrogen production ability and working stability of solid oxide electrolyzer.    DETAILED DESCRIPTION - Nickel oxide powder, yttria-stabilized zirconia powder and pore-making agent are mixed uniformly, and pressed in a mold into hydrogen electrode sheet. The obtained sheet is sintered at 800-1100 degrees C for 1-5 hours, to obtain electrolyte film support. The mass ratio of nickel oxide powder to yttria-stabilized zirconia powder is 0.8:1-2:1. Yttria-stabilized zirconia (YSZ) powder electrolyte film (a) is coated on the surface of the electrolyte film support, thickness of the YSZ electrolyte film is adjusted to 4-100 mu m, sintered at 1000-1400 degrees C for 1-20 hours to reduce the size of nickel oxide-YSZ hydrogen support/YSZ electrode sheet and YSZ electrolyte layer (a) is formed on the surface of the electrode film support. The YSZ electrolyte film (b) is coated on the surface of the YSZ electrode layer (a), thickness of the YSZ electrolyte film (b) is controlled to 2-15 mu m, and sintered at 1250-1400 degrees C for 1-20 hours, to form YSZ electrolyte layer (b) on the surface of the electrolyte film support. The sintered YSZ electrolyte layer (a) is compact and YSZ electrolyte layer (b) is a porous structure. A lanthanum-strontium-manganese-YSZ pulp is coated to the electrolyte of nickel oxide-YSZ hydrogen support/YSZ electrode sheet by screen printing or pulp coating, sintered at 1100-1250 degrees C for 2 hours, to obtain oxide electrolyzer cell electrode sheet having thickness of 10-100 mu m.