The invention discloses chili pepper sauce and a preparation method thereof. The chili pepper sauce is prepared from the following raw materials in parts by weight: 10-15 parts of fructus gardeniae, 20-25 parts of moringa seeds, 15-20 parts of nardostachys roots, 20-25 parts of lysimachia sikokiana, 15-20 parts of holy basil, 10-20 parts of laurel leaves, 25-30 parts of fructus tsaoko, 10-15 partsof rhizoma kaempferiae, 20-25 parts of carrot, 20-23 parts of mung beans, 20-25 parts of kelp, 25-28 parts of black fungi, 20-25 parts of pepper, 3-5 parts of crystal sugar, 30-35 parts of black rapeseed oil, 20-25 parts of fermented soybeans, 5-10 parts of peanut kernels, 25-30 parts of preserved pickled mustard tuber, 20-22 parts of potherb mustard, 20-25 parts of onions, 15-18 parts of garlic,18-20 parts of fresh ginger, 15-20 parts of star anise, 10-15 parts of Chinese prickly ash, 35-40 parts of chili peppers, 60-80 parts of rice wine, 18-20 parts of shiitake mushrooms, 20-23 parts of cucumbers, and 15-20 parts of salt. The preparation method of the chili pepper sauce comprises the following steps: S1, performing preliminary treatment on the raw materials; S2, preparing a fermentedmixture; S3, carrying out stir-frying; and S4, carrying out sterilizing, weighing, bottling, packaging and warehousing.