This study focuses on the wood anatomy of 60 Khaya ivorensis A. Chev. (Meliaceae) trees from natural forests in three forest zones of southern Ghana. The arrangement, grouping, density and diameter of vessel elements in stem wood were measured and theoretical hydraulic conductivities were calculated for each site. Also anatomical characteristics of thin branches damaged by mahogany shootborer (Hypsipyla robusta Moore) were studied with special reference to effects on vessel element diameter, vessel density and hydraulic conductivity. Our study revealed that there were significant differences in vessel element diameters and hydraulic conductivities between the sites, and that the water conduction efficiency of K. ivorensis wood increased with increasing annual precipitation. In shootborer damaged branches mean vessel element diameters were consistently smaller and mean theoretical hydraulic conductivities lower than in undamaged branches. This suggests that Hypsipyla damage can have a negative effect on the growth rates of mature African mahogany trees in natural forests.