The invention relates to cooling chili sauce and a preparation method thereof. The preparation method comprises the following steps: firstly, an appropriate amount of vegetable oil is heated in a pot until smoke comes out, and garlic and fresh gingers are added to be stir-fried to be fragrant; soybean sauce is added to be stir-fried until the soybean sauce is dark in color and emit fragrance, chili powder is added, the mixture is continuously stir-fried for 5-10 minutes, and fire is turned off; after the fire is turned off, moringa oleifera leaf powder and fructus phyllanthi powder are immediately added, the mixture is stirred evenly, the stirred mixture is filled, the filled mixture is sealed, and the sealed mixture is sterilized to obtain the finished products. When the cooling chili sauce is tasted, the spiciness can be felt in the mouth and lip, and also be felt in the tip of the tongue, but the throat part can feel cool and sweet. The spicy piquant taste is very light, after the chili sauce is eaten in the stomach, no sense of excitement is felt in the stomach, and no hot sense is felt. The chili sauce has sweet and sour tastes, and is long in aftertastes, good in palatability, and free of a moringa oleifera flavor. The provided chili sauce is spicy to mouth, but does not have spicy sense in heart, feels cool and non-irritable in belly after the chili sauce is eaten, does not cause internal heat, constipation and other symptoms, and is a good choice for people who love spicy tastes.