Abstract: We researched on the stomatal differentiation,stomatal density and stomatal aging in Amaranthus tricolor leaves.Result shows that the differentiation of mother cell in protective cell begins from folded leaves that are 13.8 mm long.With the leaves unfolding,stomata are mature and open.The differentiation of stomata is continuous process in amaranth leaves.When leaf's length is 27 mm and leaf's area is 1.18 cm²,the stomatal density is max.The stomatal aging and degradation are also found in the old leaves of the lower part.

Key words: Amaranthus tricolor, stomata, development