Anatomical changes in the root, stem, and leaf of soybean (Glycine max (L.) Merr. cv. Nazlican) plants under drought stress were studied by light microscope and their significance was evaluated by numerical analysis. Some anatomical features related to parenchymatous cells, diameter of tracheas belonging to the root, stem, and leaf; stomata index; and size and average number of stomata and epidermal cells were found to be important characters varying in soybean plants under stress. These characters were also statistically significant. Leaf water potential (Chi(leaf)), root:shoot ratio, total chlorophyll content, and stomatal conductance were measured. Chi(leaf), total chlorophyll content, and stomatal conductance were lower while root:shoot ratio was higher in stressed plants compared to the unstressed ones. It has been concluded that some anatomical and physiological changes occurred in soybean under drought stress.