Abstract: The ultrastructure of the sex pheromone of Clania variegata was examined by use of the transmission electron microscope. Each pheromone gland cell has a cuticular pore and an end apparatus, bounded by microvilli, but there is no duct cell, nor real cuticular ductule. The cuticle above the gland cell is obviously produced by the intermediate cell. The secretions of the gland cell are released from the end apparatus through the pore to the exterior of the body. Thus, it has been further confirmed that the sex pheromone gland cell of Clania variegata is a new type of insect epidermal gland cell. Based on morphology and fuctions of all types of insect epidermal gland cells, this paper also discusses their possible ways of evolution.