LiNi0.4Co0.2Mn0.4O2 samples was synthesized via urea co-precipitation method. The XRD, SEM and electrochemical measurements were used to examine the structure,morphology and electrochemical characteristics, respectively. LiNi0.4Co0.2Mn0.4O2 powders show excellent electrochemical performances. The optimum sintering temperature and sintering time are 800°C and 20 h, respectively. The LiNi0.4Co0.2Mn0.4O2 powders shows the discharge capacity of 145.1 mAh·g-1 in the range of 3.0-4.5 V at the first cycle, and the discharge capacity remains 132.3 mAh·g-1 after 30 cycles. The urea co-precipitation method is suitable for the preparation of LiNi0.4Co0.2Mn0.4O2 cathode materials with good electrochemical performances for lithium ion batteries.