Dengue 2 virus was found by transmission electron microscopy to be present in the reproductive tissues of male Aedes aegypti (L) 14 d after intrathoracic inoculation. Dengue 2 particles were detected in the matrix, epithelial cells, and the peripheral fat body of the testes; secretory droplets of columnar cells of the accessory glands; and the epithelial and muscle cells of the seminal vesicles. However, none was found in the germ cells (i.e., spermatogonia, spermatocytes, spermatid, or spermatozoa). These observations indicate that fluid transfer may be the mechanism of venereal transmission of dengue 2 virus by Ae. aegypti.