The invention relates to the field of animal feed additive, in particular to a layer feed additive. The layer feed additive is characterized by comprising according to the weight parts: 60-80 of spirulina powder, 10-15 of garlic powder, 20-30 of licorice powder, 2-5 of calcium glycerophosphate and 0.01-0.05 of citric acid; superfine crushing is carried out for the spirulina powder, garlic powder and licorice powder; subsequently, according to the proportioning, the crushed raw materials are mixed uniformly with the calcium glycerophosphate and citric acid; subsequently, sterilizing, cooling and packaging operations are carried out to prepare the layer feed additive. The layer feed additive can provide sufficient nutritional compositions such as calcium element, phosphorus element, selenium element and the like for the layer, improve the immunity of the layer, balance the gastrointestinal microbial community, provide balanced nutrition, is easy to be absorbed and utilized and has low price.