SMS Lützow was the second Derfflinger-class battlecruiser built by the German Kaiserliche Marine before World War I. Ordered as a replacement for the old protected cruiser Kaiserin Augusta, Lützow was launched on 29 November 1913, but not completed until 1916. Lützow was a sister ship to Derfflinger from which she differed slightly in that she was armed with an additional pair of 15 cm (5.9 inch) secondary guns and had an additional watertight compartment in her hull. She was named in honor of the Prussian general Ludwig Adolf Wilhelm von Lützow who fought in the Napoleonic Wars.

The Derfflinger class was a class of three battlecruisers of the Imperial German Navy. The ships were ordered for the 1912–13 Naval Building Program of the German Imperial Navy as a reply to the Royal Navy's two new Lion-class battlecruisers that had been launched a few years earlier. The preceding Moltke class and the incrementally improved Seydlitz represented the end of the evolution of Germany's first generation of battlecruisers. The Derfflinger class had considerable improvements, including a larger primary armament, all of which was mounted on the centerline. The ships were also larger than the preceding classes. The Derfflinger class used a similar propulsion system, and as a result of the increased displacement were slightly slower.