The effect of ecological factors and their interactions on quantitative changes of 20 anatomical and two morphological traits of leaves in six different populations of Alnus subcordata C. A. Mey. in the west and east of the Hyrcanian forests in three elevation classes include lowland, midland and highland were analyzed and compared. Leaf area, glandular trichomes, thickness of cuticle cells, and stomatal density decreased from west to east and were significantly different in three classes of altitude. There is a positive correlation between traits. Leaf thickness and thickness of adaxial epidermal cells, from west to east, were also significantly influenced by the interaction of ecological features. The decrease rainfall from west to east and altitude have affected the mentioned anatomical traits. Thickness and width of palisade cells, thickness of spongy cells, number of spongy layers and the thickness of the main veins from east to west were not significant, but in terms of elevations, their differences were significant. Also, there was a positive correlation between leaf area, stomatal density, glandular trichome maximal length, cuticle thickness and vein thickness. Number of adaxial collenchymas layers of vein, thickness of vein abaxial parenchyma cells, number of abaxial parenchyma layers of vein and thickness of vascular bundle of vein also increased significantly as altitude increased. Various types of stomata have also been observed in this species.