Braye Harbour (also known as Alderney Harbour) is the main harbour on the north side of the Island of Alderney, in the Channel Islands, a dependency of the British Crown. A 3,000 feet (910 m) break-water was built by the Admiralty to protect the Navy in the 19th century shelters Braye Harbour. It is an artificial harbour created by building a pier or jetty. The harbour faces out onto the Swinge, which is part of the English Channel. It is here that most of the island's freight comes in. It is more or less a suburb of St Anne, which is a large settlement in Alderney that juts out on a rocky promontory on the west side, approximately 1 mile from the harbour.

The harbour precinct contains harbour facilities, a knitwear factory, a sailing club, toilets, and several places offering food and drink.

The 3,000 feet (910 m) breakwater at Braye Harbour was built by the British to protect ships of the Navy between 1847 and 1864. Originally, two arms were planned as a protection to the harbour from the tidal race of The Swinge, but only the western arm was completed due to improving relations with the French. When construction stopped the breakwater was 4,827 feet (1,471 m) long, but within a year 1,780 feet (540 m) was abandoned to the sea following heavy gales. It gives only partial protection to the harbour, as during storms the breakwater suffers damage and is constantly repaired and maintained. Financial assistance for maintenance was provided by the UK until the 1980s, and since then by Guernsey in lieu of defense payments required to maintain The Bailiwick of Guernsey's status as a British Crown Dependency. The massive stone breakwater is generally used as a walk way to enjoy the scenic beauty of the bay, its harbour and the sea. The breakwater is now termed as "Victorian" and it provides safety to yachtsmen who sail in the harbour.