Abstract: The changes of structural characteristics and submicroscopic structure of epidermis of tobacco leaves during mature stage grown at different altitudes were studied with field experiments,and the effects of altitude on the growth,development and quality of tobacco leaves were also discussed.The results showed that:with the ascant of altitude,the accumulation of starch grains in chloroplasts and stoma density inclined to decrease and the number of epidermal glandular trichome,cell wall thickness,intracellular osmiophilic material,and the volume and number of vesicle inclined to increase;while the structural integrity and the number of granum lamella of chloroplast appeared to be consistent.