The invention relates to a process for manufacturing a disc, in particular to a process for manufacturing opening discs of a separator, which comprises the following working procedures: blanking, blanking round stock, punching fabrication holes, rotary extrusion, edge turning, punching splined holes, punching evenly distributed holes on a conical surface, spot welding of ribs and polishing, wherein a heat treatment working procedure adopting annealing is added between the rotary extrusion working procedure and the edge turning working procedure, and the annealing temperature is between 700 and 800 DEG C and the heat preservation time is between 5 and 15min. Because the process for manufacturing the opening discs of the separator increases the heat treatment working procedure, the internalstress is eliminated fully, the atom dislocation is greatly recovered, the plasticity is improved obviously, and the aim of reducing deformation of openings of the discs is achieved; and the process retains certain deformation strengthening function, so parts have certain hardness and strength to meet the requirement on service performance of the parts.