Fresh-cut fruits and vegetables have a short shelf life and are prone to contamination by foodborne pathogens.In this study,fresh-cut lettuce was used as the test material,and based on single factor and orthogonal experiments,the preservation effect of slightly acidic hypochlorous water(SAHW)on fresh-cut lettuce and its influence on storage quality were studied.Using four factors SAHW available chlorine concentration,treatment temperature,treatment time and treatment method,on the basis of single factor experiments,a four-factor three-level orthogonal test was conducted to verify the effect of the best treatment on the sensory quality,total bacterial count,ascorbic acid(Vc)content and Malondialdehyde(MDA)content of fresh-cut lettuce during storage.The results showed that SAHW had a good preservation effect on fresh-cut lettuce,and the influencing factors were the treatment method>treatment time>effective chlorine concentration of SAHW>treatment temperature.The best preservation treatment was shaking and soaking in the SAHW with an effective chlorine concentration of 50 mg/L for 5 min at 15℃.Under this treatment,the sensory score was 5.22,the a* value was-2.73,and the total bacterial count was 3.79 lg CFU/mL.This treatment maintained effectively the sensory quality of fresh-cut lettuce during storage.On the 25th day of storage,the total bacterial count was only 0.72 lg CFU/mL(indicating the inhibition of the growth of bacterial colonies),Vc was 14.5 mg/100 g,and the MDA was 0.26 nmol/g,indicating the reduction of Vc loss and MDA accumulation significantly and extension of the shelf life of fresh-cut lettuce.The results provide a scientific basis for SAHW to be used as a preservative agent for fresh-cut lettuce.