Disclosed is a method for separating and purifying Ginkgolide C from root bark of ginkgo. The method comprises: (1) extracting the root bark of ginkgo with ethanol; (2) concentrating the resulting extract under vacuum to remove ethanol; (3) separating the concentrate by macroporous resin column chromatography; (4) after the concentrate being loaded on the column, washing the column with pure water to remove impurities, and then eluting the column with an ethanol solution; (5) concentrating the eluate under vacuum to dryness to obtain a yellow crude extract; (6) heating the crude extract in water to boiling to form a solution, and then refrigerating the solution; (7) concentrating the supernatant solution and filtering under vacuum to obtain a mixed crude crystal of ginkgolides; (8) dissolving the crude crystal in ethanol to form a supersaturated solution, refrigerating and crystallizing the solution to remove Ginkgolides A and B; (9) concentrating and recrystallizing the mother liquor to obtain a crystal of Ginkgolide C; and (10) recrystallizing the crystal with ethanol several times to obtain a high-purity crystal of Ginkgolide C.