'Malta Due' was an Italian naval attack on the port of Valletta on the island of Malta (26 July 1941).

Undertaken by the 10a Flottiglia MAS after the original 'Malta' of 26 June had been cancelled as a result of adverse weather, the operation had as its object the sinking of British surface warships and submarines as a means of weakening the British capability to use naval forces to continue the decimation of the Italian supply convoys crossing the Mediterranean Sea to North Africa. The 'Malta Due' attack used four Motoscafo Armato Silurante (torpedo-armed motor boat) or MAS light torpedo boats, six 2-ton Motoscafo da Turismo Modificato (modified tourist motor boat) or MTM assault motor boats generally known to their crews as barchini) and two Siluri a Lenta Corsa (slow-running torpedo) or SLC manned torpedoes, known to their crews by the nickname maiale (pig).

The approach of the Italian force was detected, by a British radar installation, at a comparatively early stage of its approach to Malta. The British coastal artillery batteries held their fire until the Italian craft had approached to close range, and then opened fire to kill 15 of the Italian sailors, including Capitano di Fregata Vittorio Moccagatta, the commander, and capture of another 18 sailors.

Maggiore Teseo Tesei and a petty officer named Alcide Pedretti reached the coast on a maiae but were killed near Fort St Elmo as they attempted to destroy the outer defences of the harbour. Tenente Franco Costa and Sergente Luigi Barla on the other maiale became lost, scuttled their torpedo and swam ashore at St George’s Bay, two miles (3.2 km) to the north-west of Valletta. The scuttled maiale was recovered by the British and examined in great detail as this was the first such vehicle to be recovered intact.

Thus all six MTM craft, both SLC craft and two of the four MAS torpedo boats (MAS-451 and MAS-452) were lost, one of the last being found adrift by the British and towed to port by a seaplane.

This tactical disaster forced the 10a Flottiglia MAS to undertake a major reassessment of its operations, with Capitano di Fregata Ernesto Forza succeeding Moccagetta as the unit’s commander and Capitano di Fregata Junio Valerio Borghese becoming commander of the underwater weapons group.