The invention discloses a biomass curing-forming fuel. The biomass curing-forming fuel consists of straws, saw dust, coal dust, a combustion improver, a sulfur-fixing agent and a dust-falling agent according to parts by weight, wherein the straw is one or combination of the straw of crops such as rice, wheat, soybean, corn, sorghum, cotton, rape and tobacco, a branch and a bark of trees and shrubs, rice hull, chaff and peanut coat; the combustion improver is one or more of table salt, sodium nitrate, potassium permanganate, potassium oxide, sodium nitrite and sodium hypochlorite and capable of realizing decomposition and combustion supporting at different temperatures; the sulfur-fixing agent is in a manner that sodium carbonate, calcium hydroxide and alkyl alcohol amine compounds are synergistically used and is capable of reducing discharging of sulfur dioxide; and the dust-falling agent is selected from iron sesquioxide and capable of lowering a melting point of ash and reducing dust volume. The biomass curing-forming fuel has the advantages that the combustion efficiency is high, the slag bonding and the soot formation are not generated, the black smoke is little, the fire power strong, the combustion is sufficient, the ash does not fly, the biomass curing-forming fuel is clean and sanitary and the like. The invention further discloses a preparation method of the biomass curing-forming fuel.