Technical Abstract: Varroa destructor Anderson and Trueman 2000, an ectoparasite of honey bees, causes huge economic losses to apiculture annually. Its role as a vector of diseases is thought to involve the salivary glands as the terminal organs of transmission. The salivary glands are paired, oval, non-acinar organs, closely attached to the base of the gnathosoma and enveloped in a sheath of unknown embryological origin. Ultrastructurally, they are characterized by the surrounding sheath, and cells that have a strong presence of rough endoplasmic reticulum, irregular-shaped nuclei, and secretory spheres surrounded by an otherwise electron-lucent cytosol. Secretory spheres are sparse in most peripheral cells and heavily converged about the apical membranes of interior cells. Interior cells are positioned radially about the internal duct cells. The internal ducal lumen is narrow and brush-bordered. The membranes between the ducal lumen and the gland cell cytoplasm are fused and ruptured, allowing the salivary spheres to pass into the interior duct for secretion through the exterior duct. Bacterial biofilms are associated with the spheres and the rupture. Virus particles and endosymbionts are also present in the glands. The external duct remains uncharacterized, but the assumption that its embryonic origin is the same as that of the internal duct and surrounding gland cells is questioned.