The invention provides micromolecular biological feed. The micromolecular biological feed is prepared from the following components in mass percent: 10%-20% of nano concentrated enzyme, 50%-70% of composite liquid molasses and 10%-40% of a composite carrier. According to the micromolecular biological feed, macromolecular organic matters in the liquid molasses are hydrolyzed by a nano concentratedenzyme technique, so the viscosity of the liquid molasses is quickly reduced; due to addition of a nano material, the dispersity is better when the liquid molasses is prepared into a solid product; and simultaneously, the addition of the carrier with strong water absorptivity can enlarge the specific surface area of the liquid molasses, so the liquid molasses subjected to the nano concentrated enzyme treatment is easier to mix with the carrier and dry. The product is minimum in nutrient component loss through low-temperature baking, the degraded macromolecular organic matters in the liquid molasses are more favorable for animals to digest and absorb, the finished product is easier to transport and preserve, and also the range of application of the product in animal feed is greatly extended.