Abstract: Anatomical structure of stem of Ipomoea cairica was observed in detail by using light microscopy . The results indicate that the anatomical structure of the stem of Ipomoea cairca compose mainly of primary structure , and the cambiums has formed , but the secondary structure is not well-developed . The stem of Ipomoea cairica usually bears 3 - 6 cavitys, which may be schizogenous secretory canals . The tangertial wall of epidermis cells gets ticker , and the epidermis has cutide, stomas and air chamber . In cortex , there are 1 - 3 layers of cells tightly next to the epidermis as well as the 1 - 3
layers of cells which are deep inside cortex, both of them are secretory cells . The vascular bundles are bicollateral . The xylem is well-developed , and the vessel elements arrange so closely that they become a circle surround the phloem and pith . In the middle of stem is the pith , which composed of abundant parenchymatous cells with rhombohedral crystals .

Key words: Ipomoea cairica