The invention relates to a piglet premix as well as a preparation method and an application of the piglet premix. The feed premix is prepared from the following components in parts by weight: 5-10 parts of Pudilan, 10-20 parts of butyrin, 10-30 parts of citric acid, 10-20 parts of white sugar and 20-65 parts of lactose. Compared with the prior art, the piglet premix does not contain an antibiotic; various components are good in compatibility; escherichia coli is inhibited from multiple dimensions of promoting development and maturing of piglet intestinal mucosa, maintaining an intestinal acid environment, providing lactation energy, resisting bacteria and diminishing inflammation; piglet diarrhea is avoided; and meanwhile, the acceptable daily intake of the piglets is ensured through good palatability, thereby ensuring the effect of reducing the escherichia coli in jejunums of suckling piglets, of the premix.