Preparation method for dipyridamole

The invention belongs to the chemical field, and particularly relates to a preparation method for dipyridamole; diethanol amine and 2,6-dichloro-4,8-dipiperidinopyrimidino[5,4-D]pyrimidine are subjected to a reaction at relatively low temperature to generate dipyridamole, the dipyridamole crude product is subjected to secondary refining, and the yield and the chemical purity of the finally obtained dipyridamole are respectively increased to 94% or more and 98% or more; and the preparation method has the advantages of mild reaction, high reaction efficiency, low cost and the like, and is suitable for wide promotion and application.