Objective To observe the in vitro susceptibility test result of ceftazidime/avibactam (CZA) combined with aztreonam (ATM), as well as imipenem (IPM) and meropenem (MEM) respectively combined with ceftazidime (CAZ), cefoperazone/sulbactam (SCF), amikacin (AK), levofloxacin (LEV) and fosfomycin (FOS) to KPC-, NDM- and IMP-producing carbapenem-resistant Enterobacterales (CRE). Methods 38 non-repetitive CRE strains were isolated from clinical specimens. The minimal inhibitory concentration (MIC) of antimicrobial agents against CRE strains was determined by micro-broth dilution method. Combined antimicrobial susceptibility test was performed by the chessboard dilution method. Fractional inhibitory concentration (FIC) index was calculated to determine the combined effect. Results The MICs of CZA to 22 KPC-producing strains were ≤ 4 μg/mL, to 16 class B metallo-enzyme(NDM and IMP)-producing strains were >128 μg/mL. The synergy rate of CZA was 100% after combined with ATM. The synergy rate of IPM or MEM combined with SCF was the highest, which were 63.2% and 68.4% respectively, and the sum of synergy rate and addition rate was 100%, while the sum of synergy rate and addition rate of IPM combined with FOS was the lowest (40.5%). Among Klebsiella pneumoniae (KP) strains, the synergy rates of IPM or MEM combined with SCF were both 68%, the sum of synergy rate and addition rate was 100%, the sum of synergy rate and addition rate of IPM combined with FOS was the lowest (24%). Among Escherichia coli (ECO), the synergy rates of IPM or MEM combined with SCF were 44.4% and 77.8% respectively, the sum of synergy rate and addition rate was 100%, the sum of synergy rate and addition rate of IPM combined with FOS was the lowest (66.7%). Among genotype KPC strains, the synergy rates of IPM or MEM combined with SCF were 72.7% and 63.6% respectively, the sum of synergy rate and addition rate was 100%, the sum of synergy rate and addition rate of IPM combined with FOS was the lowest (22.7%). Among genotype NDM strains, the synergy rates of IPM or MEM combined with SCF were 46.7% and 80.0% respectively, the sum of synergy rate and addition rate was 100%, the sum of synergy rate and addition rate of IPM combined with FOS was the lowest (64.3%). All combined schemes had no antagonistic effect. Conclusion CZA alone or in combination with ATM is effective for CRE strains. Among all the combinations of IPM and MEM respectively with other antimicrobial agents, the sum of synergy rate and addition rate of IPM and MEM combined with SCF is the highest, and the sum of synergy rate and addition rate of IPM combined with FOS is the lowest. Not all combination schemes are effective. The effect of different combination schemes on the same strain is different, and the effect of the same combination scheme on different strains is also different. The dose ratio between two agents is also important.