The invention discloses a mouthwash containing lysozyme, which comprises the following raw materials in parts by weight: 1-3 parts of lysozyme, 1-1.5 parts of ferulic acid, 10-15 parts of polyethylene glycol, 12-20 parts of glycerin, 1-3 parts of carboxymethyl pachyrhin, 1-3 parts of trehalose, 1-3 parts of glycine, 2-4 parts of pearl powder, 2-4 parts of aloe vera gel, 0.2-0.5 parts of sodium chloride, 0.2-0 parts of sodium alginate 0.5 parts, 0.4-0.6 parts of xylitol, 0.4-0.6 parts of citric acid, 0.1-0.3 parts of mint essence and 180-220 parts of deionized water. At the same time, a preparation method of mouthwash containing lysozyme is provided, which includes: crushing, mixing; ultrasonic treatment, stirring reaction; calcining, adding lactic acid, stirring reaction; mixing, sterilizing, and filling. The invention can effectively improve the stability of the mouthwash while maintaining the activity of lysozyme.