The objective of this work was to investigate the variability in chemical composition of wood of some poplar clones aged from 6 to 8, obtained at Poplar Research Institute in Novi Sad. Wood samples were taken from different height of stem and regarding to standard analyses of main chemical constituent of cell wail wood tissue: cellulose, lignin, and pentozanes, as well as extractives and ash content. Interclonal variability of chemical composition was determined by statistical methods.There are significant differences between the contents of all individual components of wood chemical composition.