A process for preparing tanshintotalphenolic acid and the use of the product are disclosed. The process comprises: tanshin is hot-extracted with water, the extract is separated and refined by polyamide column and macroporous adsorption resin column, and lyophilized to obtain tanshintotalphenolic acid. The yield of the final end product is more than 4 percent based on the amount of crude drug and the content of totalphenolic acid is more than 80 percent. The tanshintotalphenolic acid obtained can be used as the medicine for preventing and treating cerebrovascular and cardiovascular diseases and so on.