The synthetic method of a new antithrombotic drug-prasugrel was introduced in this paper. The precursor(Ⅹ) of condensation reaction was synthesized via four steps from 4,5,6,7-tetrahydrothieno[3,2-c]pyridine hydrochloride. Another precursor (Ⅻ) of condensation reaction was synthesized via two steps from 1-(bromomethyl)-2-fluoro benzene. The target product was prepared via condensation, hydrolysis and acetylatio n reactions from the two the precursors. The yield of all synthetic steps is 34.6%. The partly intermediate product and target product was identified by 1H NMR and MS. The synthetic process, featured with simple operations、high yield and easy purification, is not less than the synthetic routes reported by other papers.