Karl Klindworth (September 25, 1830–1916) was a German composer, conductor and violinist, born at Hanover.

For a time Klindworth conducted a traveling opera troupe, but settled in Hanover as a teacher and composer. From there he went to Weimar, 1852, and studied the piano under Franz Liszt. He also became on friendly terms with Richard Wagner. Among his fellow pupils were Hans von Bülow and William Mason . In 1854 he went to London, where he remained for fourteen years, studying, teaching and occasionally appearing in public. From London Klindworth went to Moscow, in 1868, to take up the position of professor of the pianoforte at the Conservatorium. While in Russia he completed the pianoforte arrangements of Wagner's Der Ring des Nibelungen, which he had commenced during Wagner's visit to England, in 1855. He also completed his critical edition of Frédéric Chopin's works. He became conductor of the Berlin Philharmonic in 1882, in association with Joachim and Bullner. He was also the conductor of the Berlin Wagner Society . He remained in Berlin till 1893, when he retired to Potsdam, practicing as a teacher. He has justly earned his great reputation as an editor of musical works. He has also very finely re-orchestrated Chopin's piano concerto, though many people still prefer the composer's own arrangement of it.

He also made a now-recorded orchestration of the first movement of Alkan's solo piano concerto (the eighth through tenth of the composer's etudes in all the minor keys), though others since have recorded all three movements.