Cleaning system and cleaning method for ultrafiltration device

The invention discloses a cleaning system and a cleaning method for an ultrafiltration device, and the cleaning system for the ultrafiltration device comprises a booster pump which is suitable for conveying a cleaning solution to the ultrafiltration device; the gas-liquid mixer is arranged between the booster pump and the ultrafiltration device, a mixing cavity is formed in the gas-liquid mixer, and the gas-liquid mixer is provided with a gas inlet, a liquid inlet and a liquid outlet which are respectively communicated with the mixing cavity; wherein the gas inlet is communicated with an external gas source, the liquid inlet is communicated with an outlet of the booster pump, the liquid outlet is communicated with an inlet of the ultrafiltration device, gas introduced from the gas inlet can be dissolved in the cleaning liquid in the mixing cavity, and separated microbubbles can act on an ultrafiltration membrane of the ultrafiltration device to clean the ultrafiltration membrane. The gas-water combined cleani