Omicron is useful to wear a mask for some protection. Although Omicron is more powerful, it is still essentially a mutation of the new coronavirus, and the mode of transmission is still through the respiratory droplet transmission. Masks can prevent the virus and its structure, masks for the outer layer of water-blocking layer, the middle of the filtration layer, the inner side of the water-absorbing layer, the outer and middle layer can block droplets, the inner layer can absorb the wearer’s mouth and nose of the water, can block 0.3 to 1 pm particles, and therefore can block the virus. It should be noted that there are many types of masks on the market, you should choose medical protective masks, medical surgical masks, disposable medical masks, etc., and press the nose clip when wearing. Prevent the invasion of Omicron, in addition to the correct wearing masks, but also need to be vaccinated in a timely manner; minimize non-essential travel, in public places and take public transport more attention to the protection; collect courier must be disinfected with alcohol, and pay attention to the windows at home to ventilate.