Based on the rational univariate representation of zero-dimensional polynomial systems,Tan and Zhang proposed the rational representation theory for solving a high-dimensional polynomial system,which uses so-called rational representation sets to describe all the zeros of a high-dimensional polynomial system.This paper is devoted to giving an improvement for the rational representation.The idea of this improvement comes from a minimal Dickson basis used for computing a comprehensive Gr?bner system of a parametric polynomial system to reduce the number of branches.The authors replace the normal Gr?bner basis G satisfying certain conditions in the original algorithm(Tan-Zhang\'s algorithm)with a minimal Dickson basis Gm of a Gr?bner basis for the ideal,where Gm is smaller in size than G.Based on this,the authors give an improved algorithm.Moreover,the proposed algorithm has been implemented on the computer algebra system Maple.Experimental data and its performance comparison with the original algorithm show that it generates fewer branches and the improvement is rewarding.