Abstract: Disclosed is a method for synthesizing (S)-nicotine and an intermediate thereof, which belongs to the field of synthesizing a heterocyclic compound. A chiral amino group is introduced into 4-hydroxy-1-(3-pyridyl)-1-butanone by transaminase chiral catalysis in the presence of an amino donor to obtain (S)-4-amino-4-(3-pyridyl)-1-butanol. An N-methylation reaction is performed on (S)-4-amino-4-(3-pyridyl)-1-butanol with a methylating agent to obtain (S)-4-(methylamino)-4-(3-pyridyl)-1-butanol. The intermediate is reacted with an acylating agent or a halogenating agent to convert an alcoholic hydroxyl group into a sulfonate group or a halogen. Finally, a ring closure reaction is performed to obtain (S)-nicotine in an alkaline condition. The raw materials are cheap and readily available, the reaction conditions are mild, the operation is simple, and the cost is low.