The accumulation of nutrients (N, P, K, Ca and Mg) in biomass and their vertical distribution in 1-year-old Eucalyptus urophylla × E. grandis (DH32-29) and E. leizhou No.1 plantations growing in the same environment in Ningming County, Guangxi Province, were studied. Results showed that the mean biomass of 1-year-old E. urophylla ×E. grandis and E. leizhou No.1 were 13.70 and 12.06 t·hm–2. The stem wood component accounted for the largest portion of total tree biomass, whilst the leaf component and root component were markedly smaller. In terms of nutrient concentrations, all five nutrient elements were at their highest levels in the leaves of E. urophylla ×E. grandis and E. leizhou No.1, followed by bark, branches, and roots, whilst they were at their lowest levels in stem wood. Overall, N content was highest, K and Ca contents ranked second, and the Mg and P contents were lowest. The total nutrient accumulations in the E. urophylla × E. grandis plantation at age 1 year was 124.84 kg·hm–2, which was lower than that of the E. leizhou No.1 plantation of the same age at 132.76 kg·hm–2. The amount of nutrient elements in different parts of trees was in the order: leaves > branches > bark >stem-wood > roots for the E. urophylla × E. grandis plantation, and branch >leaves > bark > stem-wood > roots for the E. leizhou No.1 plantation. The nutrient utilization efficiency of the 1 year old E. urophylla × E. grandis plantation was a little higher than that of the E. leizhou No.1 plantation.%对广西宁明县相似立地条件下1年生尾巨桉(DH32-29)和雷林1号桉幼林的生物量和5种营养元素(N、P、K、Ca 和 Mg)积累量及其分配特征进行了研究。结果表明：1年生尾巨桉和雷林1号人工幼林林分生物量分别为13.70和12.06 t·hm–2，不同器官生物量均以树干最大，树叶或树根最小。两种桉树不同器官中营养元素含量均以树叶最高，其次是树皮、树枝和树根，树干最低，林木不同器官中营养元素含量均以 N 最高，其次是 K 和 Ca，Mg 和 P最低。1年生尾巨桉幼林营养元素积累量为124.84 kg·hm–2，略低于雷林1号桉幼林(132.76 kg·hm–2)，5种营养元素积累量在尾巨桉人工林的分配为树叶＞树枝＞干皮＞干材＞树根，在雷林1号桉的分配为树枝＞树叶＞干材＞干皮＞树根。尾巨桉幼林营养元素利用效率略高于雷林1号桉幼林。
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