Using reference of the conception of Gini coefficient—the target was used to evaluate the impartiality of earnings, and the way was put forward to evaluate the equity of total pollutant load allocation for water bodies in Huizhou city. Gini coefficient method was used to analyze the effection of targets such as the population, GDP, water resource, water environment capacity to the allocation. The rationality was evaluated by the Lorenz curves of correlative factors. According to Gini coefficient method, the plan was decided to reduce the quantity of mainly water pollutions. The results indicated that Lorenz curves of water resource can focus on the key areas of water pollution in districts in Huizhou city correctly and also provide the basis for gross water pollutant reduction.