The invention provides a preparation method of fiber health food, and relates to the field of foods. The fiber health food is prepared from the following raw materials in parts by weight: 16 parts of lycoperdales, 25 parts of soybean milk, 3 parts of glycerol, 13 parts of broad beans, 5.2 parts of water chestnut stems, 17 parts of clanis bilineata larvas and 30-45 parts of rice wine. The preparation method of the fiber health food comprises the following steps: preparing dry lycoperdales powder, dry vegetable powder and clanis bilineata larva powder; and then, carrying out mixing, so that the fiber health food is prepared. The fiber health food disclosed by the invention contains no chemical component and traditional Chinese medicine components which may cause side effects to the human body, so that the fiber health food is suitable for long-term usage; the fiber health food contains edible bacterium, crop, wild plant and insect raw-materials, so that the fiber health food is rich in vegetable protein, animal protein, cellulose and various trace elements needed by the human body which are all acquired from the food materials; thus, the fiber health food is capable of comprehensively complementing the nutrients need by the human body. Animal and human feeding function trials have proven that the fiber health food has the health-care functions of helping to improve memory and reinforce body resistance; thus, the fiber health food is suitable for the young children, the mental workers and the memory-declined older people who have the need of improving memory.