Lobster feed with high conversion rate capable of purifying water and preparation method of lobster feed

The invention discloses a lobster feed with high conversion rate capable of purifying water and improving meat quality. The lobster feed is prepared from the following raw materials in parts by weight: 6-8 parts of meat powder, 4-6 parts of wheat middling, 3-4 parts of water caltrop, 4-5 parts of Chinese knotweed herb, 3-5 parts of spirulina, 20-26 parts of sweet potato skin, 5-8 parts of saw dust, 3-5 parts of oyster meat powder, 12-16 parts of fried soybean meal, 1-2 parts of salt, 4-6 parts of cuttlefish meal, 2-4 parts of pagoda leaf powder, 6-8 parts of rice sprouts, 6-9 parts of dry arenicola cristata powder and 6-10 parts of an assistant. The lobster feed disclosed by the invention is high in conversion rate; the added raw materials such as the oyster meat powder and dry arenicola cristata powder are rich in a plurality of proteins and amino acids, so that metabolism can be effectively promoted; the immunity of the lobsters can be enhanced by contained unsaturated fatty acid; and the raised lobsters are extremely high in nutrient value, and significant in economic benefits.