The invention discloses a low-
energy consumption good-durability 
biomass briquette fuel. According to the invention, the pretreated corn straws are taken as a 
raw material for anaerobic 
fermentation for 10-20 days, so that mechanical endurance of the 
briquette fuel is increased, finally, 
biogas residue is dried and crushed, and then is composited with an anti-slagging agent and an oxidant and other active ingredients for compression moulding under condition of 6MPa. The preparation method has the advantages of fast moulding and less required pressure, and is helpful for reducing equipment wearing. In the invention, 
magnesium carbonate is taken as the anti-slagging agent, during a 
combustion process, the 
Mg element and elements such as Si, K, and Na which are inherent in the corn straws and are capable of slagging are subjected to a reaction, a novel 
compound K2Mg(SO4)2 is generated and provides anti-slagging performance to the 
briquette fuel, waste diesel oil taking as an ignition-assisting agent is used for increasing the 
combustion efficiency and 
heat energy of the fuel, and the produced briquette fuel has the advantages of low 
energy consumption, high calorific value, firm quality, tight structure and good durability, easy initial ignition, less 
smoke, and long consumption time.