The invention discloses biomass compact briquette fuel and a preparation method thereof. The biomass compact briquette fuel is prepared from the following raw materials in parts by weight: 50-80 parts of wheat straw, 35-45 parts of corncobs, 20-30 parts of pine needle, 10-15 parts of sawdust, 5-10 parts of traditional Chinese medicine residue, 8-14 parts of fish meal, 12-18 parts of palm shell, 4-8 parts of sawdust, 5-10 parts of camellia seed cake, 7-14 parts of soybean oil, 6-12 parts of bone meal, 10-15 parts of coconut coir and 15-20 parts of peanut shell. The biomass compact briquette fuel is prepared from the multiple raw materials such as the wheat straw, the pine needle, the sawdust and the traditional Chinese medicine residue by grinding, mixing, drying, compressing, cooling and packaging, so that the problems of great demand for one raw material and difficulty in collection of the single raw material can be solved; the heat value of the fuel can also be obviously increased; the unit heat value of the fuel can reach 6000 kilocalorie; when being burned, the fuel is smokeless, tasteless, clean and environment-friendly; and the combustion ratio of the fuel can reach above 98%, the using cost of the fuel is far lower than that of petroleum energy sources, and the biomass compact briquette fuel can be widely applied to industrial and agricultural production, electricity generation, heat supply and heating, boilers and the like and has a wide application prospect.