Cubic spinel Co2SnO4 nanocrystals are successfully synthesized via a simple hydrothermal reaction in alkaline solution. The effect of alkaline concentration, hydrothermal temperature, and hydrothermal time on the structure and morphology of the resultant products were investigated based on X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It is demonstrated that pure Co2SnO4 nanocrystals with good crystallinity can be obtained in NaOH solution (2.0M) at 240°C for 48h. The galvanostatic charge/discharge and cyclic voltammetry were conducted to measure the electrochemical performance of the Co2SnO4 nanocrystals. It is shown that Co2SnO4 nanocrystals exhibit good electrochemical activity with high reversible capacity (charge capacity) of 1088.8mAhg−1 and good capacity retention as anode materials for Li-ion batteries, much better than that of bulk Co2SnO4 prepared by high temperature solid-state reaction.