Apocynaceae is a useful family comprising of trees notable for different medicinal remedies. Consequent to their importance vis-à-vis scarcity in the forest, they are being sold in various Nigerian markets by herb sellers mostly in sterile and fragmentary forms. Hence, the medicinal plants are subjected to adulteration and substitution. Frequently, identification of the plants by users is basically with the aid of floristic markers, which are not readily available for such purpose. It, therefore, becomes pertinent to carry out the taxonomic revision of these trees to provide additional markers that will contribute to their effective identification for correct use. Various documentations have been made on members of apocynaceae and are properly placed on their respective taxa using epidermal traits. However, such information is scarce for Alstonia boonei, Holarrhena floribunda, Rauvolfia vomitoria, Thevetia nerifolia and Vocanga africana. This study therefore aimed at providing epidermal taxonomic markers that could be employed in delimiting the species as an alternative when the fruit or floral parts are wanting. Leaf epidermises of five (5) species of apocynaceae representing 5 genera were studied under a Biological microscope with a camera attachment. Data obtained were statistically analyzed. The epidermal cell was penta or hexagonal in A. boonei and V. africana. The stomatal length varied from 20.88 µ m (R. vomitoria) to 25.92 µ m (T. nerifolia) and 18.96 µ m (R. vomitoria) to 29.28 µ m (V. africana) on the abaxial and adaxial layers respectively. All the epidermal characters on the adaxial layer were significantly different (p<0.05) among the species. Anticlinal walls were sinuated in H. floribunda and T. nerifolia while in R. vomitoria, it was straight to wavy. V. africana and A. boonei anticlinal walls were straight. This study represents the first account of epidermal characterization of the members of apocynaceae in Nigeria and is of taxonomic importance in setting boundaries among the species.