Namulonge is located within the bimodal rainfall region. It is at 00 32'' N of the Equator and 320 37'' E. It is 27 km North of Kampala at an elevation of 1150 metres above sea level. It has a tropical wet and mild dry climate with slightly humid conditions (average 65%). The vegetation is wooded savanah with tall trees and tall grasses dominated by (Pennisetum purpureum and Parnicum maximum). This location is ideal for testing annual crops as the two rainy seasons of approximately the same length (3 months each) offer the chance to carry out trials twice a year. The Institute comprises the main station at Namulonge and is served by a research station at Kalengyere and Sub-station at Kigumba, situated in South Western Uganda and Masindi respectively. Kalengyere is the centre of solanum potato research in Uganda.
NAARI originally has 1188 hectares of land, 187 hectares at Sendusu of which hosts the IITA Eastern and Southern Research Centre.