Carbon-doped TiO2 nanotubes were synthesized through a sol–gel and subsequent hydrothermal process. Transmission electron microscopy and X-ray diffraction showed that the products are uniformly straight tubes with the diameter around 10nm in anatase-type. The electrochemical performances of the nanotubes were tested by constant current discharge/charge, cyclic voltammetry, and electrochemical impedance spectroscopy. The initial discharge capacity reaches 291.7mAhg−1 with a coulombic efficiency of 91.7% at a current density of 70mAg−1. There is a distinct potential plateau near 1.75 and 1.89V (versus Li+/Li) in the lithium intercalation and extraction processes, respectively, and the lithium insertion capacity is about 204mAhg−1 over the plateau of 1.75V region in the first cycle. From the 2nd to the 30th cycles, the average reversible capacity loss is less than 1.73mAhg−1 per cycle. After 30 cycles, the reversible capacity still remains 211mAhg−1 with a coulombic efficiency larger than 99.7%, implying a perfect reversibility and cycling stability.