•Ultrasound can enhance the decontamination effect of chemical disinfectants, and effectively remove the biofilm of bacteria.•Ultrasound-assisted thermal technology can effectively reduce the number of food-borne pathogens in ready-to-eat foods.•Ultrasound can enhance the mass transfer process, increase the penetration rate, and shorten the dehydration and curing time.•Ultrasonic cooking promotes the oxidation of proteins and lipids to enrich the flavor of meat products.•Ultrasound and ultrasound-assisted traditional tenderization technology can effectively improve the tenderness of meat. With the increase in food standardization and the pace of modern life, the demand for ready-to-eat foods is growing. The strong processing conditions of traditional technology often accelerate the rate of deterioration of quality, and microbes are the safety hazard of ready-to-eat foods. Ultrasound technology is an environmentally friendly technology that hardly causes thermal damage to raw materials. In this paper, the ultrasound technology is used in the disinfection, sterilization, enzyme inactivation, desensitization, dehydration, curing, tenderization and cooking process of fresh food from the perspective of microbial safety and quality of fresh food. The cavitation effect of ultrasound can improve the mass transfer rate of infiltration processes such as dehydration and curing, promote the oxidation of lipids and proteins for enrich the flavor of meat products, improve the microbiological safety and reduce the sensitization by destroying the integrity of the microbial cells and the conformation of the protein. In addition, ultrasound as an auxiliary processing technology can reduce the damage of traditional production technology to reserve the quality and nutritional value of food. Ultrasound has proved to be an efficient and green processing technology for ready-to-eat food.