The invention relates to a cattle and sheep ultrafine particle feed licking brick and a preparation method thereof, and the licking brick is characterized in that each kg of the licking brick comprises the following raw materials: 0.10-0.15g of ferrous sulfate, 0.10-0.15g of zinc sulfate, 0.07-0.10g of copper sulfate, 0.12-0.16g of manganese sulfate, 0.01-0.02g of sodium selenite, 0.05-0.15g of potassium iodide, 0.01-0.03g of cobalt chloride, 0.05-0.15g of magnesium oxide, 2-5g of chromium nicotinate, 30-150g of sodium sulfate, 50-100g of calcium hydrophosphate, 50-250g of extruded corn seed powder, 200-300g of common salt, 200-300g of bentonite and 60-100g of molasses. The substances adopt ultrafine smashing. The preparation method combines the chemical coagulation technology and the mechanical pressing technology and simultaneously carries out the ultrafine smashing treatment on the formula raw materials, so that the licking brick has the advantages of a wide range of sources for selecting a curing agent, low cost, more comprehensive nutrition, greater density, reasonable feed intake, sustained release of elements, health care, safety and environmental protection, thereby being suitable for raising levels with different feeding methods.