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Cinnamomum Camphor is a very important species for greening and beautifying in southern city. Ancient C. Camphor objectively records the social development and species change, however, its aging is increasingly serious. Based on nutritional deficit theory, we analyzed 12 kinds of mineral elements in leaves of ancient C. Camphor with different growth potential, in order to find the key elements caused aging and provide theory basis of aging evaluation and regeneration. Results showed that, there was difference in the contents of Mg and Fe between different season, but no significant difference in the others. Significant difference existed in all elements between different trees. When dij was 5 (dij means Euclidean distance), the tested C. Camphor could be divided into 3 grades (I, II and III, respectively) according to growth potential (from strong to weak) by clustering analysis. With senescence aggravating, the content of Na and Al in leaves increased, while the others decreased, and the ratio of N, P and K was imbalanced seriously. By principal component analysis, three main components were extracted, whose accumulative total variance contribution rate was 94.91%. The variance contribution of the first principal component was 69.25%, including P, K, Cu, Fe, Mg and B. The second principal component was N, its variance contribution was 13.45%. The variance contribution of the third principal component was 12.21%, including Ca, Al, Zn and Mn.
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