This article is about the Swan River in Australia. For other meanings, see Swan River (disambiguation).

View from Kings Park over Perth Water

The Swan River estuary flows through the city of Perth, in the south west of Western Australia. Its lower reaches are relatively wide and deep, with few constrictions, while the upper reaches are usually quite narrow and shallow.

It was named by the Dutch explorer, Willem de Vlamingh in 1697, after the famous black swans of the area.

The Swan River drains the Avon and Swan Coastal catchments, which have a total area of about 121,000 km². The Avon River contributes the majority of its freshwater flow. The climate of the catchment is Mediterranean, with mild wet winters, hot dry summers, and the associated highly seasonal rainfall and flow regime.

The estuary is subject to a microtidal regime, with a maximum tidal amplitude of about one metre, although water levels are also subject to barometric pressure fluctuations.

The river is a popular place for viewing the annual Australia Day fireworks, with over 400 000 people crowding the foreshore, Kings Park and boats on the river.

The Noongar believe that the Darling Escarpment is said to represent the body of a Waugal - a snakelike being from Dreamtime that meandered over the land creating rivers, waterways and lakes, it is taught that the Waugal created the Swan River.