A detailed characterization of soils earmarked as “Benchmark Soils of Morogoro District”, Tanzania, was carried out to provide data required for planning and execution of soil fertility studies and transfer of agro-technology in the area. Benchmark soils are defined as those occurring in extensive areas and whose comprehensive characterization could contribute substantially to transfer of agro-technology from one area to another. Eleven sites were selected as “Benchmark Sites” of the district based on existing soils information coupled with reconnaissance field soil survey. Soil samples representative of the benchmark soil profiles were described and analysed for their chemical, physical and mineralogical characteristics. Based on these data, general fertility is discussed for the various soils pointing out their potentials and constraints. The data also permitted classification of the soils using international soil classification systems i.e. the United States Department of Agriculture Soil Taxonomy and the FAO-UNESCO Soil Classification System. The soils were classified into different categories reflecting their differences in potentials and constraints and hence use and management. The data obtained through this study presents a substantial base for sound land use planning and will facilitate transfer of technology from one area to another with similar ecological conditions.