For obtaining different shape of presoma Co3O4 of positive pole material of Lithium-ion battery, such as sphere, polyhedron, octahedron Co3O4, they could all be obtained in different atmosphere and different heat treatment system. The atmosphere included covering and uncovering, and the inputting of different nitrogen ratio. The heat treatment system included constant and changeable. The result showed, plan 1: Increasing temperature 2h, keeping temperature 5h(it was adjusted at 850℃), while it was cooled in the furnace to 285℃, then it was cooled in the opening air, good sphere shape presoma could be gotten; While nitrogen: air=25%:75%, the oxygen content of the baked atmosphere was 15.75%, good polyhedron-shape Co3O4 could be obtained; When nitrogen: air=50%:50%, the oxygen content of the baked atmosphere was 10.5%, good octahedron -shape Co3O4 could be acquired, and the octahedron Co3O4 grew at the style of corkscrew spin.