As-prepared anatase TiO2 with different particle sizes are heated in a lithium hydroxide solution to form Li–Ti–O precursors by using hydrothermal method. Spherical Li4Ti5O12 powders with different particle sizes are obtained by calcining the precursors at 800 °C. The X-ray diffraction (XRD) indicates that elevated hydrothermal reaction temperature and higher concentration of lithium hydroxide solution eliminate the content of impurity in the final product. Scanning electron microscopy (SEM) shows the obtained powders have regular spherical morphology. The obtained Li4Ti5O12 with particle size of about 0.5 μm exhibits excellent electrochemical performance, and the initial discharge capacity reaches 165 mAh g−1 at 35 mA g−1 (0.2 C) and more than 97% of the initial capacity is retained after 70 cycles.