Kalungu District is bordered by Gomba District to the north, Butambala District to the northeast, Mpigi District to the east, Masaka District to the south and Bukomansimbi District to the west.The 'chief town' of the district, Kalungu, is located 21 kilometres (13 mi), by road, northeast of the city of Masaka, the largest metropolitan area in the sub-region. The coordinates of the district are:00 06S, 31 49E.

The relief of Kalungu District is generally low and flat and its altitude ranges from 900-1200m above sea level . Relative Relief is low, not more than 21m above sea level. In most cases the interfluves are broad flat or rounded and marrum covered, and the valleys are wide. The drainage system is dominated by river Katonga flowing from Lake Victoria

Kalungu district has  ferralitic and hydromorphic soils. The dominant soils in the ferralitic type are reddish-brown and sandy- loams; and loams on laterite. They are very acidic with pH value below 5, deficient in available phosphorous and all the major exchangeable bases. They are good for growing bananas, beans, maize,and cassava.