Variation in structural composition of Guinea savannah vegetation was investigated in Kpashimi forest reserve, Niger State, Nigeria. Field work inventory was conducted to determine the current status of the vegetation physiognomic characteristics of the six physiographic units in the study area; comprising of Riparian Forest, Savannah Woodland, Degraded forest Scrubland, Grassland, and Bare surface. Parameters measured include tree density, trunk diameter, basal area, tree density, tree species diversity, tree height, crown cover, shrub cover, and grass cover. The aim of the study is to determine and compare the variation in structural characteristics of the vegetation of the study area. Analysis of variance (ANOVA) showed significant differences amongst virtually all the parameters among the physiographic units. In general, the landscape of the forest reserve has been influenced significantly by anthropogenic disturbance and the resulting landscape vegetation cover is a mixture of natural and human managed mosaics that vary in shape, size, structure and arrangement. Thus, drastic measures need to be taken so as to reverse the trend and to mitigate the far reaching ecological consequences of vegetation degradation as highlighted in this study. Access to UNFCC carbon credit is hereby recommended for the management of the study area.