The invention discloses heat-stress-resistant fermented feed for a laying hen. The heat-stress-resistant fermented feed is prepared from the following raw materials: corn, soybean meal, cottonseed meal, apple pomace, chili meal, corn steep liquor sprayed corn husk, wheat bran, bacteria liquid, compound premixed feed and water, wherein the bacteria liquid is prepared from enterococcus aureus, bacillus subtilis, saccharomyces cerevisiae, brown sugar and water. The preparation method of the heat-stress-resistant fermented feed comprises the following steps: crushing the raw material, mixing the dried material, preparing the bacteria liquid, secondarily mixing the wet feed, and conducting anaerobic fermentation. The heat-stress-resistant fermented feed disclosed by the invention has the following benefits: the main essential nutrients in the fermented feed are approximate to that of complete feed for the laying hen and comprise active beneficial bacteria, gamma-aminobutyric acid, organic acid and other active factors; the feed can be added to the daily ration of the laying hen based on the rate of 5-15% to obviously improve the laying rate of the laying hen, the feed-gain ratio, the broken egg rate and the oxidation resistance, synergistically give play to multiple action of the beneficial bacteria on microecologic control to bacterial flora in the gastrointestinal tract, nerve regulation to the central nervous system by the neurotransmitter, and buffering of the organic acid to respiratory alkalosis due to high temperature, and obviously resist against the heat stress due to high temperature in summer for the laying hen.