The work aims to improve the corrosion resistance of high temperature alkaline black film on low-carbon steel substrate processed by ultrasonic shot peening. The severe deformation layer was obtained by ultrasonic shot peening on the surface of low-carbon steel to achievegrain refined structure. The alkaline black films were prepared on the shot-peened and unshot-peened samples. The effects of shot peening on the morphology and corrosion resistance of the coatings were studied through microscopic observation, electrochemical polarization curve, electrochemicalimpedance spectroscopy and immersion test. The microstructure of the surface of low-carbon steel was significantly refined and more uniform after the ultrasonic shot peening. The ultrasonic shot peening promoted the formation of fine, uniform and compactmicrostructure of the black film. Compared with the black film on unshot-peened samples, after ultrasonic shot peening, the free corrosion potential of the film increased by 170 mV, the corrosion current density reduced by 85%, film resistance increased by 1 time and the ability of resistance to salt waterwas improved. The ultrasonic shot peening can be used in the surface pretreatment of the low-carbon steel to improve the corrosion resistance of the subsequent black film.