According to the study on the biomass of Chinese fir mixed genealogy stand and the rule of the whole biomass distribution among different organs. The biomass of the mixed genealogy stands at the age of 8, 12, 16, 20 years for Yang Kou area was respectively 92. 855, 154. 819, 217. 128 and 234. 876 tons per hectare. The ratio of the bole biomass in the whole biomass increased with the age increasing. The ratio various of the branch leaves biomass in whole biomass was not obvious after some age stage. The ratio of root biomass in the whole biomass decreased with the age increasing, but the root biomass did not vary with the age after some age stage. The whole biomass of mixed genealogy stands was 1-2 times as higer as control stands under same condictions. The age of quantity mature of mixed genealogy stands was 3-4 years later than control stands. The range of distribution and absorb of mixed genealogy root systems were deeper and wider than control root systems. The growing diferent between mixed genealogy and control was not obvious after 20 years old. The mixed genealogy could be better suitable for fast growing and high yield plantation.