Barrow Island is an area, current Town Council and former district-level ward of Westmorland and Furness, Cumbria, England. Originally separate from the British mainland, land reclamation in the 1860s saw the northern fringes of the island connected to Central Barrow. Barrow Island is also bound to the south and east by the town's dock system and to the west by Walney Channel. The Ward population taken at the 2011 census was 2,616.

Whilst still an electoral ward for Barrow Town Council, the ward was combined at a district/ local authority level with Central and Hindpool wards in April 2023 following formation of the new Westmorland and Furness local authority and be named 'Old Barrow'.

The name of the town of Barrow-in-Furness is believed to derive from the Norse word Barrae, meaning Bare Island, which actually referred to Barrow Island. Since the 1860s the island has been connected to the mainland as its channel was modified to form two docks, the Buccleuch Dock and the Devonshire Dock. The remainder of its channel has also now been developed as part of the dock system. The island is also known as 'Old Barrow'.

The Second World War defences constructed around Barrow Island have been documented by William Foot. They included a number of pillboxes to defend the docks. The principal threat was seizure of the docks by airborne troops; a seaborne landing was thought to be highly unlikely unless Ireland was occupied first.

During the late 19th century when most of Barrow Island's tenement housing was constructed the majority quickly became occupied by Scottish and Irish working class immigrants who worked at the town's shipyard, steelworks and jute mill.

Still classed as one of the Islands of Furness, Barrow Island is characterised by densely constructed tenement housing alongside huge industrial buildings. The area is home to the vast majority of Barrow's shipyard including the Devonshire Dock Hall complex - the main occupier of the reclaimed land from Walney Channel. In 2011, the ward's population stood at 2,616 which although relatively small compared to Barrow's other wards equates to a higher population density, and twice the national average. The island has become notorious for its high unemployment rate and a number of other social issues which saw it feature in a 2009 episode of The Secret Millionaire.

Barrow Island, which is nicknamed 'Baz I' locally, is served by a primary school, nursery school, two churches, several pubs, post office, pharmacy and a number of small supermarkets. Work is currently underway to convert a former shipyard canteen/arts centre into two new retail units with office space.

With a previous unoccupancy rate of 80%, 320 of the apartments have been converted into serviced accommodation called 'The Maritime Apartments', costing around £5 million to refurbish. These are popular with contracted BAE workers, offshore wind farm and rig engineers and those in the construction industry. The land surrounding the apartments and along the main roads has benefited from a £1 million landscaping project to create parks, open spaces and growing areas. These are now known as the 'Maritime Streets'.