Dimethyl carbonate (DMC) is one kind of important solvent for lithium battery electrolyte. The purifying method of DMC is crucial for obtaining high purity product of it. Using a green and sustainable technology makes more sense in the face of increasing environmental burdens. In this study, a static layer melt crystallization method was used to achieve the purification of high purity DMC from a mixture of DMC and its major impurities. The partial binary phase diagrams between DMC and the main impurity - methanol (MT) - were determined using differential scanning calorimetry (DSC) method. Effect of process parameters such as crystallization temperature, cooling rate, sweating temperature, and heating rate on the distribution coefficient Kf and yield Y were evaluated using One-factor-at-a-time (OFAT) experiment and response surface experiment, respectively. The phenomenological relationships between different parameters and distribution coefficient and yield were discussed and revealed. Eventually, under the optimized process conditions, the purity of DMC was increased from 96 % to 99.847 %, and the single yield could reach 70 %.