The invention relates to a feed for increasing production performances of lactational house-feeding sheep and a preparation method thereof, relating to a feed. The feed is prepared from the following raw materials: instant noodle residues, soybean hull, DDGS (Distillers Dried Grains with Soluble), molasses, urea, peanut meal, cottonseed meal, silage corn straws with the moisture content of 65%, dry peanut vines and additives. The preparation method disclosed by the invention comprises the following steps: adding water into the crushed peanut meal and cottonseed meal, and fermenting by introducing aspergillus niger and bacillus natto to obtain a fermented mixture A; introducing saccharomyces cerevisiae into the crushed instant noodle residues, spreading to be flat, and carrying out aerobic fermentation to obtain a fermented mixture B; adding water into crushed peanut straw sections, adding the soybean hull and the DDGS to mix, and adding the urea and the dried additives to mix again so as to obtain a mixture C; and adding the molasses to mix after mixing the fermented mixture A, the fermented mixture B and the mixture C so as to prepare the feed for increasing the production performances of the lactational house-feeding sheep. The feed is easy to absorb and can be used for increasing the milk production of lactational sheep and the milk quality.