In this study， the morphology， physiology and transcriptome of different types of leaves were measured in adult trees of Silver Poplar， which provided a reference for revealing the maturation effect. The main results are listed： （1） The leaf morphology at long branches and short branches was significantly different， and the leaves in different parts overlap to a large extent. （2） The in different parts of leaves was significantly different， and the content of chlorophyll a and total chlorophyll in the lower leaves were significantly higher than those of the upper and middle parts. The SOD enzyme activity in the lower leaves was significantly higher than that in the upper and middle parts. The MDA content was manifested as the middle > upper > lower par；.The starch content in lower leaves was significantly lower than that in upper and middle leaves； The IAA content of the leaves in different parts increased with the decrease of height， and the ABA content was the middle > the upper part > the lower part； The IAA and IAA/ABA of leaves at the long branches were significantly larger than those of the short branches， and the ZR content showed an opposite trend. （3） The number of differentially significant genes between different parts of leaves was less than the number of differentially significant genes between different types of leaves based on transcriptome data screening. （4） GO and KEGG enrichment analysis of different genes in each comparison group showed that the genes significantly enriched in the photosynthetic pathway in the upper long branching leaves relative to the lower long branching leaves （SC-vs-XC） and in the upper short branching leaves relative to the lower short branching leaves （SD-vs-XD）， and gene annotation of two of these genes showed that both genes encoded PsbR proteins， and the gene expression was up-regulated in the lower leaves. The expression of these two genes was found to be up-regulated in the lower leaves， and the analysis of the growth hormone transduction process showed that the expression of the genes was up-regulated in the shorter leaves.