In this paper, clean coal was recovered from tailings by flotation with the aid of ultrasonic irradiation. Flotation test, coal surface scanning and collector adsorption measurement were carried out. The results show that ultrasonic alleviated slime coating and decreased collector adsorption on coal surfaces. Meanwhile, the combustible recovery increased while the recovery of ash-formed minerals decreased. Particles with different size and density fractions have different flotation behaviors, which were also analyzed by measuring size fraction distribution and density fraction distribution of clean coal. This practice saved coal resources and benefitted environment.