Like other countries in the Sub-Saharan Africa, Uganda is not an exception to the effects of land use/cover changes on the environment. Specifically the study intended to; determine the magnitude and trend of land use/cover changes in Kanungu District for the last 35 years. A series of Landsat TM/ETM orthorectified satellite imagery of 1975, 1987 and 1999 were classified using unsupervised classification procedures in ILWIS 3.3 software to determine the magnitude and trend of land use/cover changes. A total of 65 local residents were randomly selected for questionnaire administration with the help of village leaders to examine the underlying drivers of land use/cover change. The results showed that the magnitude of small scale (Non-uniform) farming largely increased by 5% from 1975 to 1999 while areas covered by Tropical high forest relatively decreased by 16% between 1975 and 1987 but slightly increased by 1% in 1999. The areas covered by wetlands comparatively increased by 4% from 1975 to 1987 and by 1999 they slightly decreased by 3%. The woodland areas decreased by 3% from 1975 to 1987 and to some extent also increased by 2% in 1999. Household size, type of crops grown, customary land tenure system, availability of agricultural extension workers, weak environmental laws and policies are significant predictors of land use/cover change in Kanungu District.