SANAE IV is a current South African Antarctic research base located in Vesleskarvet, Queen Maud Land. The base is part of the South African National Antarctic Programme (SANAP) and is operated by the South African National Antarctic Expedition.

The other two SANAP bases are located on the Gough and Marion islands.

Located in the Queen Maud Land region of Eastern or Greater Antarctica, SANAE IV is on top of a distinctive flat-topped nunatak, Vesleskarvet, on the fringe of the Ahlmann Range of mountains. The base is approximately 80 kilometres (50 mi) from the edge of the continent (also known as the grounding line or hinge zone) and 160 kilometres (99 mi) from the edge of the ice shelf. Vesleskarvet is completely surrounded by the glacial ice sheet.

The first three SANAE research stations were located on the Fimbul Ice Shelf near the coast, and were subject to the gradual snow burial and eventual crushing that occurs with all stations constructed in this fashion. With a vision of creating a more permanent station, SANAE IV was completed in 1997 using a design which was revolutionary at the time - a structure raised on stilts which allows snow to blow through underneath and thus limits deposition.

By constructing the base near the cliffs of Vesleskarvet, the concept was advanced further: snow that would collect downwind of the base and eventually advance to cover it is instead blown off the 250 m high cliffs into the wind-scoop beyond. By virtue of this feature, the station should far exceed the short useful life of its predecessors, and the raised design has since been applied to newer stations, such as the British Antarctic Survey's new Halley Research Station and Germany's new Neumayer Station III.

The station has an orange coloured roof for better visibility from the air. The underside of the station used to be painted in a blue colour which in theory was warmed somewhat by the sun and contributed to reducing the build-up of ice underneath the station. In 1999 the South African minister of Environment and Tourism decided that this colour scheme is too reminiscent of South Africa's old flag, and ordered the orange roof to be painted bright red. Eventually, the roof remained orange and the blue underside was painted orange as well.

SANAE IV consists of three linked modules, each double-story, 44 metres (144 ft) long and 14 metres (46 ft) wide. Two smaller nearby structures contain the satellite dish used for communications and the diesel fuel bunkers. Joined end-on-end in a north–south orientation, the base modules are complemented on the northern end by a large raised helicopter landing area with a lifting section allowing vehicles to be brought up into the hangar for maintenance.

C-block, the northernmost module, contains the large hangar, generator room, workshop, water storage, sewage processing plant, equipment stores, offices of the mechanical and electrical engineers, flight operations office, gymnasium and sauna. The neutron monitors of the North-West University are also housed in this area.