A method for aerobically air-drying sludge cakes is provided. The method comprises: crushing and dispersing sludge filter cakes into a layer of sludge granules, blowing with positive pressure dry air into the layer of sludge granules moving at low speed or overturned so that the sludge granules experience aerobically exothermic reactions, which make moisture rapidly evaporate from sludge granules and moved to the dry air by mass transferring under the effect of both the external heat and internal heat, physically or chemically sterilizing the sludge granules moving at low speed or overturned, pumping out tail gas by negative pressure from the layer of sludge granules, washing and then discharging, and further pulverizing the dried sludge granules to reach the reclamation requirements. At the same time, an apparatus for carrying out the method is also provided. The method is high in heat conducting and mass transferring efficiency when drying and low in energy consumption for drying. It accelerates the drying speed. The sludge granules can be stably and safely processed during the drying. In addition, the dried tail gas can meet the environment-friendly discharge standard, and the output sludge is good for sludge reclamation.