The Rumpler C.III (factory designation 6A 5) was a biplane military reconnaissance aircraft built in Germany during World War I.

[1] It was a development of the Rumpler C.I design incorporating many aerodynamic refinements, including wing planform, airfoil section, and horn-balanced ailerons,[2] revised empennage,[2] and new rear fuselage decking with compound curves.

[3] This latter feature was later removed and replaced with a simplified structure, at which point the factory designation was changed to 6A 6.

[3] Performance was improved over that of the C.I,[1] and the C.III was selected for limited production, thought to be about 75 aircraft.

The C.III was a qualified success, but its design served mainly as a stepping stone to the further refined C.IV.