The invention discloses a preparing method for coconut sauce. The preparing method comprises the steps that coconut juice is fermented through lactobacillus, coconut flesh and the like are added and subjected to pulping, and then the coconut sauce is prepared through the heating sauce stewing technology; stewing concentrating, filling and the like are carried out. According to the preparing method, the two constitutions of the coconut juice and the coconut flesh of coconuts are fully used, the nutrient ingredients of the coconut sauce are increased through lactobacillus fermentation, the immune regulating function is achieved, and the flavor of the coconut sauce is increased; by means of the heating sauce stewing technology, the fragrance of the coconut sauce is remarkably enhanced, the obtained coconut sauce has sweet aroma and is mellow and natural, meanwhile, part of polysaccharide generated through lactobacillus metabolism reacts with the added protein through the technology, macromolecules with the hydrophilic and oil-wetness natures are generated, a stable system of the coconut sauce is formed, and the shelf life is guaranteed. The obtained coconut sauce is natural and healthy and conforms to the development direction of the market.