A complete ration, or diet, suitable for beef cattle in different fattening stages is provided, as well as a method for formulating the ration. All by-products of sugar manufacture are recycled and used to formulate the complete ration for beef cattle in different fattening stages, using sugarcane tip leaves and alkalized bagasse as raw materials, using molasses and corn flour as energy feed, using peanut bran, soybean residual, rapeseed meal, etc., as protein feed, using carbamide, dicalcium phosphate, limestone powder, strain and pre-mixture as other additives. The complete ration suitable for beef cattle in each growing stages can be flexibly formulated according to nutrients requirements of beef cattle in different growing stages. Comparing to the regular feed for the same fattening stage, the complete ration described can lead to a lower production cost and a lower ratio between feed and weight, and bring higher economic values.