The invention relates to a room temperature magnetic cooling system and application thereof, the room temperature magnetic cooling system comprises a cool end heat exchanger, a hot end heat exchanger, a fluid distributing disc, a magnetic field system, a cooling bed and a step motor, characterized in that the cooling bed is a circular ring body which is a hollow cavity and is divided into four chambers on the ring, each of which is provided with two openings for entrance and exiting of the fluid on the upper and lower part, two opposite chambers are in series connection with each other, the inlet is connected with the outlet at the bottom, each chamber is filled with magnetic cooling materials; the magnetic system comprises an inner magnetic device and an outer magnetic device, the inner magnetic device is made of permanent magnet and provided within the circular ring body of the cooling bed, the outer magnetic field device is formed by combining two permanent magnets with arc-shaped surfaces, the two permanent magnets are externally provided with yokes, the outer magnetic field device is provided outside the circular ring body of the cooling bed and forms a closed magnetic path with the inner magnetic field device; a main shaft of the step motor traverses centre of the inner magnetic field device to fix with the inner magnetic field device; shaft end of the main shaft is fixed with the fluid distributing disc; the cold end heat exchanger is connected with the hot end holes for entrance and exiting of the cooling bed. The invention has the advantages of advancing of running frequency of the magnetic cooling machine, thus improving cooling efficiency and cooling temperature difference, and the invention is compact in structure and steady in running.