In agricultural life cycle assessment (LCA), the choice of allocation methods to spread out impacts between coproducts is an important issue, as they may induce different conclusions in impact levels. We proposed a biophysical allocation method to dispatch the upstream environmental burdens and the use of raw materials to the body-related coproducts of beef cattle production system at slaughterhouse stage. The method is designed to build a relationship between coproducts of the beef cattle production system and their associated net energy requirements for body growth. So it doesn't take into account the fate of the different coproducts, but only their building costs (i.e., energy needed for building tissues). A combination of metabolic growth model (Gompertz function) and models of energy cost of tissues was used to estimate the energy requirements for body growth from birth to slaughter age. The allocation factors were calculated based on the energy requirements attributed to build body tissues characterized by their chemical compositions (protein and lipid) with exclusion of waste. Finally, this method was compared with other allocation methods (e.g., physical, economic). The biophysical allocation reflects a physical and biological relationship between the coproducts as required by ISO standard. It provided a moderate allocation factor for human food due to their chemical characteristics compared to the other physical allocation methods. In addition, the data required is specific to species and less influenced within a predefined system than economic allocation. This study provides a generic and robust biophysical allocation method to handle the coproducts in beef cattle system. The method can be considered as an original contribution to the international debates on the allocation methods in LCA applied to livestock products, especially among the stakeholders of the meat value chains.