Seddon is a locality in the Australian state of South Australia located on Kangaroo Island about 151 kilometres (94 mi) south-west of the state capital of Adelaide and about 37 kilometres (23 mi) south-west of the municipal seat of Kingscote.
Its boundaries were created in March 2002 for the “long established name” which was derived from the cadastral unit of the Hundred of Seddon in which it is located.
Seddon is bounded by the Playford Highway and the town of Parndana to the north and by the South Coast Road in part to the south. The principal land use in the locality is primary production with exception to land reserved for conservation purposes as the Seddon Conservation Park and land adjoining the town of Parndana which is zoned for residential and commercial purposes.
Seddon is located within the federal division of Mayo, the state electoral district of Finniss and the local government area of the Kangaroo Island Council.