The work aims to treat banana slices with plasma activated water for different time to achieve color protection and investigate the pattern of change in properties during storage. Plasma activated water (PAW) was generated by treating deionized water with cold plasma (CP), and the changes in microstructure, storage properties, flavor substances, key enzymatic browning enzymes and reactive oxygen species levels of banana slices were measured after ultrasound-assisted PAW treatment. Compared with the control, PAW treatment enhanced the activities of polyphenol oxidase (PPO) and peroxidase (POD) during storage and improved storage properties such as hardness, moisture content, and color value of slices. According to the fluorescence results of confocal laser scanning microscope, PAW treatment promoted the level of reactive oxygen specie (ROS) in the cells of the slices. In addition, gas chromatography-mass spectrometry results showed that PAW treatment increased the percentage of esters in banana slices, while no alcohols were detected after the treatment. Scanning electron microscopy characterized that PAW treatment affected the surface microstructure of banana slices, causing the surface of banana slices to become rough, accompanied by the appearance of damage. Banana slices treated with PAW-30 s show strong antioxidant activity, better storage quality and less effect on flavor substances and microstructure. Therefore, PAW has a positive effect on the fresh-cut quality of fruits and vegetables, and the use of PAW-30 s for processing and storage of fresh-cut fruits and vegetables has a broad prospect and more environmentally friendly economic benefits.