The invention relates to a new synthetic method of an HIV-1 
protease inhibitor, 
Atazanavir, which adopts a convergent-typed synthetic strategy, introduces a construction unit, methoxycarbonyl-tert-lencyl, as an N atom 
protecting group in the whole early synthetic stage, and takes the diastereomeric 
selective reduction of 
aminoketone as the key and final 
reaction step of the new process. The method comprises the steps that: the compound of formula V, namely, N-1-[N-(methoxycarbonyl)-L-tert-
leucine]-N-2-[4-(2-pyridyl)-phenmethyl]hydrazine, and the compound of formula VI, namely, (S)-1-((S)-4-
chlorine-3-carbonyl-1-phenyl 
butane-2-yl-2-amino)-3, 3-dimethyl-1-carbonyl 
butane-2-yl-
methyl carbamate, are treated with 
nucleophilic substitution reaction to generate the compound of formula VII, namely, 1-[4-(2-pyridyl)phenyl]-5(S)-2, 5-bis{[N-(methoxycarbonyl)-L-tert-leucineyl] amino}-4-carbonyl-6-phenyl-2-azahexane; and the compound of formula VII is treated with reduction reaction to generate the 
Atazanavir. The invention has the advantages of less process 
route steps, easily-controlled 
reaction conditions, simple and convenient operation, low-price and easily-obtained 
raw material, high product yield, low cost and being suitable for large-scale production.