The density of occupied interface states as a function of energy in nonohmic polycrystalline Bi‐doped ZnO was obtained using photocapacitance measurements. Peaks in the interface states’ densities were observed at depths of 2.46 and 2.79±0.08 eV from the bottom of the conduction band. The combination of these two states was found in photoconductance measurements on Bi‐doped samples of ZnO and not found in undoped samples; thus, these states were assumed to be related to interface states that arise from doping with Bi.