Leaf indumentum and nutlet surface micromorphology of 13 taxa belonging to the Teucrium sect. Teucrium was studied with a scanning electron microscope. We observed 5 trichome types on the nutlets and 8 trichome types on the leaves. Branched trichomes were not found on the nutlets. Nutlet shapes of the taxa were elliptic, obovate, oblong, or rotund, and their surfaces were generally alveolate with different ornamentations. Some nutlets had longitudinal ridges. The indumentum varied among unrelated species and showed some significant similarities within related species. In Flora of Turkey sect. Teucrium was divided into 2 groups according to leaf fragmentation and other morphological characters. The current study supports this grouping. The indumentum types on nutlets and leaves have a high taxonomical value for the species of the genus.