To investigate tentatively the inhibition mechanism of eight monoalkylphenol flavor compounds (EMFC)， which were listed in the positive list of Chinese food additive use standard (GB2760-2014)， against Escherichia coli (EC)， and to determine the relation of the inhibition effect to the structure of EMFC， spectrophotometry， electrical conductivity and scanning electron microscope were used in this present study. The results showed all of the EMFC at the concentrations from 0.195 mg/mL to 0.781 mg/mL had effects on the production curve of EC in different degrees； EMFC enhanced the permeability of cell membrane， resulting in the leakage of intracellular ions； with the increasing of EMFC concentrations， the release of cell constituents increased. The results of scanning electron microscope indicated all of the EMFC at their minimum inhibitory concentration could damage the cell membrane and cell wall of EC to a certain extent， and make EC not the normal cell morphology but bends， folds， and depressions. The inhibition effects of EMFC on EC were associated with the structure of EMFC； the efficiency of propylphenol was better than that of ethylphenol， ethylphenol better than methylphenol. When alkyl group attached to benzene ring was same， alkylphenol whose alkyl group was at the para-position of hydroxyl group had the best bacteriostatic activity. EMFC could inhibit the growth of EC by damaging the cell membrane and enhancing the cell membrane permeability. The result obtained lays a theoretical basis for developing food preservatives by using phenol flavor compounds.