INTRODUCTION Khaya (Family Meliaceae) is widely distributed in Africa. Its trade name is African Mahogany. Three of these Khaya species are found in Nigeria. The three species found in Nigeria are the genus Khaya senegalensis, Khaya grandifoliola and Khaya ivorensis. Khaya have been found to be very useful in the treatment of arrays of diseases in Nigeria among which are malaria and sickle cell disease. OBJECTIVE They are generally referred to as Oganwo by the Yoruba tribe in Nigeria. The traditional medical practitioners find it difficult to identify hence this study. METHOD            Comparative bark anatomy and macerates of the three Khaya species was carried out to identify and describe distinctive anatomical characters that could possibly be used to delimit the taxa. Transverse section, longitudinal section and macerates of stem and root bark were made. Characteristic similarity and disparity in the tissues arrangement as well as cell inclusions were noted for description and delimitation. The anti-sickling activities of the three species Khaya bark were tested, the proximate and elemental analysis were also carried out the simple analytical procedure as described by the Association of Official Analytical Chemistry (AOAC) of 1987, 13th Edition Washington DC P1094 and Dry Ashing method of AOAC 2006 respectfully. RESULT The three Khaya species bark have anti-sickling properties with Khaya ivorensis having the highest activity with ethanolic extract KI 76.06 ± 2.72 ˃ KG 63.39 ± 0.56 ˃ KS 47.02 ± 3.63. The three Khaya species bark studied had essentially the same anatomical features.  The cuticle shape and type, epidermal cell shapes and cell inclusions reveal some similarities. The study reveals that the cuticle was striated, the shape of the cuticle ranges from circular, oval, polygonal and cylindrical elongated cell. Sclereids are present and prominent. However, there were characters that seem to be species specific in the number of outer bark cell layers, cuticle thickness, numerosity of crystal druses, types of sclereids present in the cell. The presence of stylliod crystal that is in the cell of Khaya grandifoliola distinguished it from the two other species. The proximate analysis revealed that Khaya leaves are very rich in minerals, proteins and carbohydrates. The elemental analysis showed that Khaya leaves contains essential elements within the limits of dietary requirement. CONCLUSION This study confirms the anti-sickling (inhibitory) activities of the three Khaya species with Khaya ivorensis having the highest activities in hot extraction of ethanol solvent 76.06 ± 2.72 percentage. The microscopic study of the bark of the three species revealed that there were distinctive diagnostic features that can be used in solving the identification problem of species of Khaya studied (K. senegalensis, K. grandifoliola and K. ivorensis) from one another.