The Hannover C.IV was a prototype high-altitude reconnaissance aircraft built by the during the First World War for the Imperial German Army's () Imperial German Air Service (). Completed in 1918 it was approved for service in March, but was not awarded a production contract as it offered no improvement over Rumpler C.VII (Rubild) already in service.
Derived from the two-seat CL.III, the C.IV shared the same basic conventional single-bay wing configuration with the unusual biplane tail of that aircraft. It was armed with two machine guns; one forward-firing LMG 08/15 and a flexible Parabellum MG 14 machine gun for the observer. Structurally it differed in having each wing braced with a pair of I struts that connected two points on the upper wing between the spars, one mid span and one near the tip, to a single point on the lower wing, so that from the front or rear, they appeared as a V, but from the side as an I. The aircraft was equipped with a water-cooled Maybach Mb.IVa straight-six engine that was specifically designed for high-altitude operations.
The C.IV was designed by Hermann Dorner to complete in the Inspectorate of Flying Troops ('s () high-altitude reconnaissance competition in AprilâÂÂMay 1918. It passed its acceptance trials on 19 March and was approved for service use, but it was not superior to the Rumpler C.VII (Rubild) and did not enter production. A slightly modified C.IV was tested by in June with unknown results. Sources disagree on whether one, two or five aircraft were built.