The invention discloses a method for constructing high-yield butanol bacterial strains and application thereof. The method for constructing recombinant bacteria includes suppressing or silencing genetic expression of pyruvate kinase pykA on genomes of starting bacteria for producing butanol to obtain the recombinant bacteria. The method and the application have the advantages that as proved by experiments, the yield of pyruvic acid produced by the engineering bacteria by means of fermentation can be obviously reduced, the yield of the butanol can be obviously increased, and a series of physiological indexes of cells of the engineering bacteria can be changed to different degrees.