Klebsiella pneumoniae is a well-known model organism for glycerol metabolism to produce 1,3-propanediol (1,3-PD), a valuable chemical intermediate for materials, such as polyesters. However, the relatively low conversion rate and productivity, as well as the accumulation of by-products such as lactic acid, ethanol and acetic acid, inhibit the production of 1,3-PD. Hereby, the 1,3-PD metabolism in K. pneumoniae was regulated through pathway engineering by using CRISPR-Cas9 technology for the first time to knock out the ldhA gene of lactate dehydrogenase,the adhE gene of alcohol dehydrogenase and the ack gene of acetate kinase respectively as needed and constructed recombinant bacteria ldhA(−), ldhA(−)-ack(−), ldhA(−)-adhE(−) and ldhA(−)-adhE(−)-ack(−), all of which showed a decrease in by-product production, leading to a higher NADH availability, and 1,3-BD production was significantly increased. In the shake flask fermentation, the 1,3-PD yield and conversion rate of the recombinant strain ldhA(−), ldhA(−)-ack(−), ldhA(−)-adhE(−), ldhA(−)-adhE(−)-ack(−) were higher than those of the parent strain. In the fed-batch fermentation, the 1,3-PD yield and conversion rate of the recombinant strain ldhA(−) were higher than those of the parent strain. The biomass of the recombinant strain ldhA(−)-adhE(−)-ack(−) was reduced due to the accumulation of acetic acid, but its 1,3-PD conversion rate was still higher than that of the parent strain. The higher productivity and fewer by-products concluded that the four Klebsiella pneumoniae recombinant strains could be promising industrial strain for economical production of 1,3-PD.