Abstract: Pure phase olivine-type LiFePO4 and composite cathode material LiFePO4/C were synthesized by the liquid-state co-precipitation method. The properties of LiFePO4 and LiFePO4/C were systemically studied via the methods of AAS，XRD，SEM，tapped density，etc. The electrochemical properties were tested by using analogous assembled cells. The results showed that LiFePO4 and LiFePO4/C were both simple pure phase olivine-type and the tapped density of the former could reach 1.67 g/cm3. After carbon coating，the tapped density decreased a little but had a good charge-discharge voltage plateau. Compared with pure phase LiFePO4，LiFePO4/C had better discharge capacities and excellent cycle performance，and its first discharge capacity was 158.1 mA·h/g at 0.2 mA/cm2 and even at 0.4 mA/cm2at room temperature，LiFePO4/C also had high discharge capacity of 150.0 mA·h/g. After 20 times cycling，the specific capacities were 154.2 mA·h/g，137.2 mA·h/g respectively.