The purpose of the present study was to investigate the antibacterial stability of eight monoalkyl phenol flavorants， which were listed in the positive list of Chinese food additive use standard (GB 2760-2014)， against four food-related microorganisms. Influences of temperature， ultraviolet radiation and pH value on antimicrobial stability of eight monoalkyl phenol flavorants were investigated by double dilution method. The results indicated that 2-ethylphenol， 4-ethylphenol， 2-isopropylphenol and 2-propylphenol among the eight monoalkyl phenols had better antibacterial stabilities after they were heated for 20 min under 80， 110， 121 ℃， respectively； minimal inhibitory concentration (MIC) ranges of two ethylphenols and two propylphenols to four test bacterium were 0.195-0.781 mg/mL and 0.098-0.391 mg/mL. m-Cresol， 2-propylphenol， 2-isopropylphenol and 4-propylphenol showed better inhibitory stability after ultraviolet irradiation for 20， 40， 60 min， and their MIC ranges to four test bacterium were 0.781-1.563 mg/mL， 0.098-0.391 mg/mL， 0.195-0.391 mg/mL and 0.195-0.391 mg/mL， respectively. When the pH value deviate from 7， the antibacterial activities of most of the eight phenols increased， and their MICs to four test bacterium reduced to half of the original values.