Li2MnSiO4 with different crystal structure was synthesized by solid state reaction method. Their crystal structure and electrochemical properties have been characterized by X-ray diffraction and charge-discharge test. The material prepared at 900oC in N2 atmosphere had γ-phase and its crystal structure changed to β-phase by post-heating at 400oC in air after 900oC sintering. In electrochemical measurement, two materials (γ- and β-phase) showed ~3 and ~45mAh/g, respectively. The different capacities of these two materials might be due to the change of crystal structure.