The name "Gwelup" refers to a small swamp located within the southern portion of the suburb. It was derived from the Noongar word "Gwelgannow" meaning "to shift position". Hence, Lake Gwelup was referred to as "the lake that shifts position". The name first appears in Lands Department records in 1878 as "Gwelup Swamp".
Situated on the western side of the suburb of Gwelup, lies the remainder of the once broader Lake Gwelup and accompanying bushland nature reserve. As one of the few wetlands that has a mostly intact native bushland, Lake Gwelup is home to a wide variety of local and visitor birds (waders, raptors, ducks etc.) as well many frogs (notably Moaning Frogs Heleioporus eyrei), reptile species (e.g. dugites, skinks and long necked turtles). Native flora in the bushland include Marri (Corymbia calophylla), Jarrah (Eucalyptus marginata), Flooded Gum (E. rudis), Tuart (E. gomphocephela) as well as at least four species of Banksia, many annual wildflowers (incl. orchids) and fungi. One of the most spectacular species of visiting birds is the Rainbow Bee-eater (Merops ornatus).
Throughout the wetland regions, aboriginals hunted for kangaroo, emu, snakes, tortoise, mudfish, gilgies and water birds and their eggs, to name a few food sources. Aboriginal sites are known to have existed in a few locations in the Gwelup-Balcatta region.
Gwelup is a residential suburb, with the Gwelup Plaza neighbourhood shopping centre which meets daily shopping needs. Nearby Karrinyup Shopping Centre provides other services. The suburb contains Lake Gwelup Primary School, originally opened in 1914 in two wooden school buildings which are now heritage-listed, and currently new buildings being built, Gwelup falls within Carine Senior High School's catchment area.
Gwelup Shopping Centre cnr Beach Road and Wishart Street and services the local area.
Gwelup has significant areas of public open space scattered throughout the residential area, offering meeting places and recreational opportunities for the local and wider community. Lake Gwelup, a 75-hectare (185-acre) reserve vested in the City of Stirling and centred on the 25 hectare Lake Gwelup Wetland, preserves a significant part of the natural environment, while allowing passive recreation. There are also tennis courts and cycle paths located on the Lake Gwelup Reserve.