In order to select the estimation methods of pollution load for rivers,the paper choose 8kinds of methods to calculate the load of Tongguan drawbridge section by using weekly water quality data of Tongguan drawbridge and Huaxian'' daily flow, and compared each result with the actual load respectively. The results showed that the precision of method 7is the highest.In method 7,period flux average concentration is multiplied by the period average flow to calculate the pollution load in wet,flat,dry season and then summed to calculate the annual pollution load. The paper finally proposed the improvement methods.