The invention relates to a softening process for ultra-high strength bainitic steels, wherein the ultra-high strength air-cooled bainitic steels with the tensile strength of 1300-1500 MPa are fully annealed, then tempered at high temperature, tempered and heated to 650 degrees centigrade, and air cooled to room temperature after the temperature is kept for 1.5 h. The softening process has the advantages of lower energy consumption, hardness reduced within a range of HB170-250 and high decreasing amplitude for hardness, and is capable of improving the processing efficiency of samples, prolonging to the service life of processing tools, saving energy and reducing energy consumption.