Abstract:The structure of leaf age, distribution of needle biomass in various ring branches of crowns, and the relations between needle biomass and tree heights, and timber volume increments, as well as the effects of pruning on needle biomass and growth increments in P. tabulaeformis have been studied in this paper. Seven factors related to needle biomass, namely tree height, DBH, crown length, crown size, crown/height, numbers and total length of branches, have been selected from 11 lectors by gradual regression analysis method. The best regression assessment model for needle biomass of P. tabulaeformis has been worked out and tested in the forest land of P. tabulaeformis.