Abstract: Objective To study the combination effect of fosfomycin and aminoglycosides on the formation of biofilm of Pseudomonas aeruginosa（PAO1） in vitro. Methods The modified plate culture method was used to establish biofilm model in vitro with which the morphology of PAO1 biofilms were observed by the viable counts after treated with different dosages of fosfomycin and aminoglycosides. Results MTT method showed that the viable counts of bacteria of combination gruops were significantly lower than the non-combination groups （P<0.05）. Conclusions There were obvious differences between combination fosfomycin and aminoglycosides groups and non-combination groups in the formation of PAO1 biofilm. Synergistic action of fosfomycin to aminoglycosides is verified.

Key words: fosfomycin, aminoglycosides, bacterial biofilm（BBF）, Pseudomonas aeruginosa（PAO1）