Abstract: A comparative study was conducted on the mid aged pure stands of Michelia fujianensis, Cunninghamia lanceolata and their mixed plantation in Jianou Municipality of Fujian Province to explore the influence of stand composition on the growth rate and biomass of the mid aged trees, as well as on the soil fertility. The results showed that the average DBH, average height and the average stocking of the Cunninghamia lanceolata individual trees in the mixed plantations was respectively increased by 23%, 29% and 85% compared to those of in the pure plantation. The soil fertility indexes of the mixed plantations were generally higher than those pure stands of either tree species. The total biomass of the mixed plantations was the highest and the order of this index was mixed plantation (12113 t/hm2) > pure Cunninghamia lanceolata plantations (10727 t/hm2) > pure Michelia fujianensis plantations (8450 t/hm2).