Method for extracting ptaquiloside from fiddlehead and preparing high-purity ptaquiloside

The invention discloses a method for extracting and preparing high-purity ptaquiloside from fiddlehead. The method comprises the following steps: firstly obtaining a fiddlehead water-extract from fiddlehead; preparing a ptaquiloside crude product by triple purification of polyamide 6 resin, an XAD2 column and a Chem Elut 1020 diatomite solid-phase extraction column; and further purifying the crude product by HPLC preparation and effectively separating the target compound ptaquiloside from multiple impurity phases in the fiddlehead so as to finally obtain high-purity ptaquiloside with purity being 98% and above. The product can be used as a standard product of ptaquiloside and has a wide market prospect. Meanwhile, the method is simple and convenient. Under excellent technological parameters, yield of ptaquiloside can reach 25%, production cost is low, and the product has good potential economic value.