Abstract:The growth and development of Cymbidium sinense in vitro were observed under scanning electron microscopy. The cells in mesophyll near midrib are often elongated as palisade-liked tissue in young leaves. With the development of the plantlets, cells in mesophyll near midrib of leaf base are found to be gradually rounded or elliptic, but those in leaf apex and near midrib are still arranged as palisade-liked tissue. The development of the stem goes through protocorm, rhizome and pseudobulb stages. There are a large number of starch grains in most cells of protocorm and in cells of cortex parenchyma of rhizome, but almost no starch grain is found in pseudobulb. In young roots, medullas are absent and starch grains scatter in cortex parenchyma. In mature roots, there are medullas with starch grains. Generally, of the four axillary buds, only the outmost floral bud and the innermost leaf bud are developmental.