Objective To study the antibacterial effect of Reduning combined with imipenem sitastatin sodium, cefoperazone sodium and sulbactam sodium, piperacillin sodium and ceftazidime on acinetobacter baumannii resistant to carbapenem in vitro.Methods The minimum inhibitory concentration（MIC） of Reduning and four antibiotics against 30 strains of carbapenem resistant acinetobacter baumannii was determined by broth dilution method, and the partial inhibitory concentration（FIC） index was calculated to evaluate the antibacterial effect of the drugs in combination.Results The MIC value range, MIC50 %(MIC,50,),and MIC90 %(MIC,90,) of the four antibiotics were significantly lower than that of the single drug.With Reduning 125μl/ml, cefoperazone sodium and sulbacartan sodium 32μg/ml, the number of strains was the highest and the bacteriostatic effect was the most obvious.With Reduning 250μl/ml, imipenem Cistantin sodium 64μg/ml had the largest number of strains and the most obvious bacteriostatic effect.The FIC index of ceftazidime combined with imipenemen Cistantin sodium ≤0.5 was 3.3%,0.6～0.9 was 93.3%,1～2 was 3.3%,and,>,2 was 0.The FIC index of cefoperazone sodium and sulbactam sodium FIC≤0.5 was 6.7%,0.6～0.9 was 93.3%,1～,<, 2 was 0,and ,>,2 is 0.The FIC index of piperacillin sodium≤0.5 was 13.3%,0.6～0.9 was 76.7%,1～2 was 10.0%,and ,>,2 was 0.The FIC of ceftazidime sodium index≤0.5 was 13.3%,0.6～0.9 was 80.0%,1～2 was 6.7%,and ,>, 2 was 0.Conclusion The effects of Reduning combined with four antibiotics against acinetobacter baumannii were synergistic and additive, without antagonism.Cefoperazone sodium and sulbactam sodium and imipenem Cistantin sodium had the best effect in vitro.