Franz Ignaz Danzi (15 June 1763 – 13 April 1826) was a German cellist, composer and conductor, the son of the Italian cellist Innocenz Danzi (1730–1798) and brother of the noted singer Franzeska Danzi.

Danzi lived at a significant time in the history of European music. His career, spanning the transition from the late Classical to the early Romantic styles, coincided with the origin of much of the music that lives in our concert halls and is familiar to contemporary classical-music audiences. In his youth he knew Wolfgang Amadeus Mozart, whom he revered; he was a contemporary of Ludwig van Beethoven, about whom he — like many of his generation — had strong but mixed feelings and he was a mentor for the young Carl Maria von Weber, whose music he respected and promoted.