3-Hydroxypropionic acid (3-HP) is an important platform chemical that can be used to synthesize a range of chemical compounds.To improve 3-HP production,the E.coli W3110△yqhD (pCDFDuet-tac-gpdl-TUkgsadh/pACYCDuet-tac-dhaB1-4) was genetically modified by homologous recombination technology to knockout acetaldehyde dehydrogenase (yqhD).The recombinant strain produce 2.53 g/L 3-HP of flask culture,the production was increased 5.8 times compared with original one.On the other hand,the E.coli W3110△glpR (pCDFDuet-tac-gpdlTUkgsadh/pACYCDuet-tac-dhaB1-4) was genetically modified to knockout glycerol regulatory factor (named glpR).The recombinant strain produces 2.86 g/L 3-HP of flask culture,which was 6.7 times higher than that of the original strain.Finally,the strain of E.coli W3110? glpR (pCDFDuet-tac-gpd1-TUkgsadh/pACYCDuet-tac-dhaB1-4) could produce 15.4 g/L 3-HP in a 5-L fermentor.The results provide research basis for 3-HP production.