Karl Davydov (15 March 1838 - 26 February 1889) was a Russian composer and cellist. He was born into a musical family in Latvia in 1838. Davydov was a child prodigy, but his parents demanded that he must finish his education before starting his life as a cellist. Yuly Petrovich Davidhoff, a Jewish physician and amateur musician from Courland Governorate, was the father of Davydov's mother. Mathematician and educator August Davydov was his older brother, while his nephew Alexei Davydov, a cellist and composer, was also a businessman and educator. The young Davydov studied mathematics at St. Petersburg University before turning to composition at the Leipzig Conservatory, where he studied under Moritz Hauptmann. He continued to write and perform as a cello soloist during this period. In 1863, he began teaching cello at the St. Petersburg Conservatory, where he later rose to the director position. However, the scandal prompted his resignation in 1886, and Anton Rubinstein was installed as the new leader. Aleksandr Verzhbilovich was one of several of his pupils. He planned to create an opera based on Mazeppa's story. Burenin gave Tchaikovsky his libretto after Davydov could not compose it since he had written one for him in 1880. Karl Davydov was not connected to the Davydov family that Tchaikovsky's sister Alexandra married into, despite their close association with Tchaikovsky.

Many of the most prominent composers, musicians, and members of the aristocracy knew Davydov. Count Wilhorsky, a generous supporter of the arts, gave Davydov a 1712 Stradivarius cello in 1870. Jacqueline du Pré's cello, now known as the Davidov Stradivarius, is currently on loan to cellist Yo-Yo Ma. The first piano trio by Anton Arensky and Capriccio Italien by Tchaikovsky were both dedicated to him. After completing his "cello school" book of etudes and techniques in 1888, Davydov moved on to address the physical constraints of the bow hand and playing in the upper registers when he wrote it. On February 26, 1889, Davydov died in Moscow. In 2019, a Moscow regional cello tournament in his honor was organized.