Soil samples from Dadamatti sub-watershed in northern dry zone of Karnataka were drawn at 250 m grid intervaland assessed for their fertility parameters. Analytical data was interpreted and statistical parameters like range, mean standarddeviation and coefficient of variation were calculated for each parameter. Soil fertility maps were prepared for each parameterunder GIS environment using Arc GIS v 10.4. Soils were neutral to very strongly alkaline with non saline to slightly saline. Soilorganic carbon content was low to medium. Available nitrogen was low, available phosphorus was low to medium, availablepotassium was medium to high and sulphur was low to medium. Regarding available micro nutrients, zinc and iron weredeficient in about half of the sub-watershed area whereas, copper and manganese were sufficient in the soils. The mapping ofnutrients by GIS technique in the sub watershed revealed that, available N, P, Zn and Fe are important soil fertility constraints.