The Hansa-Brandenburg W.11 was a prototype floatplane fighter designed by the Hansa-Brandenburg Aircraft Company () for the Imperial German Navy's () Naval Air Service () during World War I. It was a slightly enlarged version of the KDW fitted with a more powerful engine. Only three examples were built during 1916 and no production order followed. Their activities are not known with any detail, but one survived to the end of the war and was probably scrapped afterward.
The W.11 followed same configuration as the KDW, including the star-shaped interplane struts connecting the upper and lower wings, but was slightly larger. The latter's water-cooled Benz Bz.III straight-six engine was replaced by a Benz Bz.IV straight-six engine that also drove a two-bladed fixed-pitch propeller. The aircraft retained the KDW's armament of two fixed, forward-firing LMG 08/15 machine guns.