The anatomy, morphology and trichome distribution of leaves of two medicinal plants: Harrisonia abyssinica Oliv. and Spathodea campanulata P. Beauv. from Nigeria were studied in order to understand the usefulness of these characteristics for systematic purposes as well as provide useful pharmacopoeial information in addition to previous identification tests available on the species. Some anatomical characters such as the number and shape of epidermal cells, number of palisade and spongy parenchyma layers of the leaf blade, and the trichome types provide information of taxonomical significance. The species showed variations in stomata types, epidermal cell shape, size and trichomes morphology. Most of the characters especially trichomes were diagnostic and used for distinguishing taxa. Trichomes were mostly multicellular and glandular on adaxial surface of H. abyssinica, on the two surfaces of S. campanulata, they were glandular and non-glandular. Stellate hairs were observed in S. campanulata. Trichomes were well segmented in H. abyssinica. Trichomes of S. campanulata on abaxial surface had aggregates of 5 basalcells, in H. abyssinica there was just one basal cell. Leaf epidermal anatomy was reported for the first time in these species and was found taxonomically useful in the identification at the generic level.