The objective of this paper is to select proper synthesis route for synthesizing duloxetine hydrochloride were studied. Synthesis of this product includes synthesis of intermediate by typical mannich reaction, then perform hydrogenation reduction, and carry out chiral separation, under alk. conditions, dripping α- fluoronaphthalene, extracting by Et acetate, subsequently dripping phosphoric acid, at last, obtaining product duloxetine hydrochloride through acidifying with carbonochloride acid and hydrolization. Hence it is concluded that through anal. by IR absorption spectrum, UV absorption spectrum, NMR spectrum, mass spectrometry, etc., the synthesized sample is confirmed to be the target product.