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Spin manipulation in dilute magnetic oxide nanowires is an important topic for achieving nanometer-sized spin-based magnetic devices. In this study, single-crystalline Cu-doped and (Cu,N)-codoped In 2 O 3 nanowires were grown through a chemical vapor deposition method using In 2 O 3 and CuO powders as precursor materials. The detailed structural analyses indicate that the Cu-doped and (Cu,N)-codoped In 2 O 3 nanowires are of pure cubic bixbyite phase of In 2 O 3 . X-ray photoelectron spectroscopy provides obvious evidence that the Cu and N dopants are in the +1 and −3 valence states, respectively, and some oxygen vacancy defects are introduced into the doped In 2 O 3 nanowires. The Cu K-edge X-ray absorption fine structure spectroscopy further reveals that the doped Cu atoms are incorporated substitutionally into the In 2 O 3 host lattice at In sites without the formation of Cu metal clusters and Cu oxides secondary phases. The Cu dopants induce a large σ Cu−O 2 , which is due to the enhancement of lattice shrinkage and the relaxation of the oxygen environment of Cu atoms upon substitution. The magnetic measurements indicate that both the doped nanowires exhibit intrinsic room-temperature ferromagnetic ordering and the saturation magnetization remarkably increases in the (Cu,N)-codoped In 2 O 3 nanowires. The N codoping induces obvious spin splitting by a crystal field and strong p−d hybridization between the Cu 3d and N 2p states, which causes ferromagnetic coupling between two Cu atoms and is proved by first-principles calculations. These results demonstrate that the bound magnetic polaron mechanism plays a critical role in the observed intrinsic ferromagnetism for the (Cu,N)-codoped In 2 O 3 nanowires.