Atmosphere protection roller bottom cycle annealing furnace, mainly used for 400 series stainless steel coil in the atmosphere protection cycle annealing treatment. By the disk circle turning device, loading and unloading conveying device, annealing furnace and furnace cooling fan composition. The annealing process adopts nitrogen protection to avoid oxidation and reduce decarburization of the coil, and the surface of the material is smooth and clean after annealing; indirect heating by its own preheating burner and radiant tube, coupled with the high temperature circulating centrifugal fan and the strong convective indirect heating of the furnace conduction system, the temperature uniformity and homogeneity of the insulated coil during the heat treatment process meets the requirements; the cooling fan outside the furnace ensures that the coil is cooled down to the room temperature quickly after it is discharged from the furnace. The whole production process can be automated through L2 information docking with upstream and downstream automatic winding and uncoiling equipment.