Spilostethus pandurus is a phytophagous bug, which is widely distributed in tropical and subtropical areas. The reproductive system of the males of Spilostethus pandurus includes two testes, two seminal vesicles, two vasa deferentia, and one pair of accessory glands. The male accessory glands of Spilostethus pandurus are termed mesadenia and open into the vas deferens. The accessory glands of males (mesadenia) take an irregular shape like a sack (with multiple lobes). The mesadenia accessory glands comprise one mono-epithelial layer of secretory cells lying on a thin basal lamina and encompassed in a muscular layer. This research describes the structure and ultrastructure of the accessory glands of males using scanning and transmission electron microscopy.