Abstract: Based on the research work on the theoretical shortcomings of regular grey model-establishing method,combined with the forecast practice of gas exhaustion of a certain chemical plant,adirect model-establishing method is investigated and demonstrated.The method is formulated by using golden selection method to select background value after the linear or index alternation of originaldynamic data array. It is shown that,compared with regular grey modelestablishing method,thesuggested method possesses much more obvious superiority and rationality on the aspects of improvingthe randomness of the data array and the forecast precision. Moreover,this method helps to widenthe application of the GM(1,1)Model in environmental sciences.