Photoemission measurements on USb single crystals are reported for different excitation energies (HeI : 21.2 eV, HeII : 40.8 eV and monochromatized Al-Kα : 1 486.6 eV). A relatively strong emission at the Fermi energy is observed. From the increasing emission with growing photon energy, substantial f-character is found at the Fermi edge. The study of surface oxidation did not permit unambiguously the identification of the two emission bands at - 2.2 eV and - 5.5 eV. The surface oxidation is considered to produce a thin film with oxygen in the vacancy or interstitial places of the USb lattice