The invention discloses a purification method of pneumocandins B0 through process optimization. The method comprises the following steps: (1) acidifying fermenting liquor of pneumocandins B0, filtering the fermenting liquor and performing extraction to obtain extraction liquor; (2) adding diatomite into an extraction liquor concentrated mixture to wrap the crystals, and adding deionized water to centrifugalize so as to obtain a white solid containing pneumocandins B0; (3) dissolving the centrifugalized solid by adding ethanol, fully stirring the mixture, then adding activated carbon, fully stirring the mixture to decolor, and performing filtration to obtain a colorless filtrate; (4) concentrating the colorless filtrate till the mixture is dried, adding a heterogeneous solvent system, dissolving, and performing devitrification to obtain humid crystals; and (5) further adding the obtained humid crystals into the heterogeneous solvent system, dissolving, and performing devitrification to obtain the humid crystals and drying the same. On the basis of keeping the purity unchanged, the method not only simplifies the process steps, but also reduces the production cost, so that industrial scaled production is further facilitated.