The invention relates to the technical field of biomass fuels, in particular to biomass fuel and a production method thereof. According to the production method, the materials, such as biogas residue, crop stalks, marshal sludge and sawdust, are mixed prior to being treated via a fermentation process; thus, organics are biologically react microscopically, the materials act with one another, the structure of biomass is enhanced, crushing and compressing treatment of the materials is easier, the difficulty and energy consumption of the biomass fuel is lowered, and the cost of biomass fuel production is lowered. In addition, pulverized coal is subjected to crushing treatment and added with illegal cooking oil and gasoline; thus, the waste, the illegal cooking oil and the gasoline are made full use, the ignition point of the biomass fuel is lowered, and the ignition cost of the biomass fuel in applications is lowered.