This study was to investigate the synergistic antibacterial effect and inhibition of biofilm formation of nisin in combination with terpenes (carvacrol, cinnamaldehyde, citral and thymol) against Listeria monocytogenes. The bactericidal ranking of terpenes combined with nisin was carvacrol > cinnamaldehyde, citral > thymol. The minimum inhibitory concentration (MIC) of nisin and carvacrol when used together was determined to be 0·1563 mg ml−1 + 0·0195 mg ml−1 (nisin at MIC/2 + carvacrol at MIC/16). The addition of nisin at MIC/2 + carvacrol at MIC/2 caused more decrease in membrane potential than carvacrol or nisin at MIC individually. The decrease rates of hlyA and plcA gene expressions caused by nisin at MIC/2 + carvacrol at MIC/2 were significantly higher than those caused by carvacrol or nisin at MIC individually (P < 0·05). Nisin combined with carvacrol showed the highest inhibition activity to the formation of L. monocytogenes biofilm on stainless steel and lettuce. The inhibition effect of nisin at MIC/2 + carvacrol at MIC/16 was significantly higher than that of nisin at MIC/2 and carvacrol at MIC/16 (P < 0·05). Significance and Impact of the Study: Terpenes as important natural antimicrobials are getting considerable attention in the food industry, but their application is limited because of undesirable flavour and taste. In our study, the inhibitory effects and inhibition of biofilm formation of carvacrol, cinnamaldehyde, citral and thymol against Listeria monocytogenes ATCC 19115 were investigated when they were used individually or combined with nisin. We have demonstrated that nisin in combination with carvacrol had the best synergistic antibacterial effect and ability to inhibit biofilm formation. These observations can contribute to the effective application of these antibacterials in the food industry.