'Sunflower' was a British series of four special forces operations by the Special Air Service to sabotage railway installations in German-occupied France and so deny the Germans the use of key parts of the French railway network to reinforce their forces in Normandy just before and after the launch of 'Neptune' (iii) and 'Overlord' (5/10 June 1944).

'Sunflower I' of 5 June was directed against targets in the Brittany region, 'Sunflower II' of 7 June against targets in the Limousin region, 'Sunflower III' of 9 June against targets in the Forêt de Dunault region, and 'Sunflower IV' of 10 June against targets in the Lormes region.