We report the successful incorporation of Er(3+) ions into SnO(2) nanocrystals via a solvothermal method, with a resulting Er(3+) concentration of the order of 10(19) cm(-3). Upon excitation above the SnO(2) bandgap at 300 nm, intense and well-resolved Er(3+)-related photoluminescence (PL) at 1.55 microm was observed at room temperature. The results of PL excitation and ultraviolet/visible diffuse reflectance spectra indicate that the excitation is a carrier-mediated process with an energy transfer from the SnO(2) host to Er(3+). For the above-gap excitation, only a single type of Er(3+) luminescence center located at a centrosymmetric site was identified. The near-infrared luminescence dynamics and the weak PL thermal quenching of Er(3+) were also revealed.