Mannum is a historic town on the west bank of the Murray River in South Australia, 84 kilometres (52 mi) east of Adelaide.

Mannum is the seat of the Mid Murray Council, and is situated in the state electoral district of Hammond and the federal Division of Barker.

The Aboriginal inhabitants and traditional owners of the vicinity now called Mannum were the Nganguruku (Nganguruga), part of the larger Ngayawung community.

No Europeans visited again until 25 January 1838 when the expedition of Dr George Imlay and John Hill, on horseback from Adelaide, became the first to reach the Murray overland within South Australia.

William Randell is memorialised by the preservation of the rectangular boiler from the paddle wheeler Mary Ann in the town's recreation park.

His dry dock held the Marion, an 1897 built paddle wheeler; managed by the National Trust of South Australia as a museum.

Mannum apparently has the distinction of having lost more men per head of population in both World Wars than any other town in South Australia.

The local Community Complex hosts many various indoor sports, including basketball, squash, various martial arts and it contains a gym and other workout rooms.