The Grand Harbour is a natural harbour on the island of Malta. It has been used as a harbour since at least Phoenician times. The natural harbour has been greatly improved with extensive docks and wharves, and has been massively fortified.

The harbour mouth faces north east and is bounded to the north by St Elmo's Point and further sheltered by an isolated breakwater and is bounded to the south by Ricasoli Point. Its north west shore is formed by the Scebarras peninsula, which is largely covered by the city of Valletta and its suburb Floriana. This peninsula also divides Grand Harbour from a second parallel natural harbour, Marsamxett Harbour. The main waterway of Grand Harbour continues inland almost to Marsa. The south eastern shore of the harbour is formed by a number of inlets and headlands, principally Rinella Creek, Kalkara Creek, Dockyard Creek, and French Creek, which are covered by Kalkara and the Three Cities: Cospicua, Vittoriosa, and Senglea.

With its partner harbour of Marsamxett, Grand Harbour lies at the centre of gently rising ground. Development has grown up all around the twin harbours and up the slopes so that the whole bowl is effectively one large conurbation. Much of Malta's population lives within a three kilometer radius of Floriana. This is now one of the most densely populated areas in Europe.