Abstract: 73 Counties in Three-river watershed and upper stream of Min River are classified into 5 ecological zones by adopting numerical classification approach of ecological zone,and the possible tree species for each zone are suggested according the similarity and differences of water and heat conditions among zones.The TsPt and TsPn calculated from Miami Model reflect the differentiation of possible productivities of forest stand in study area,and reveal the conditions of water and head balance in each zone by using their ratio.