Luigi Mancinelli (Italian pronunciation: [luˈiːdʒi mantʃiˈnɛlli]; 5 February 1848 – 2 February 1921) was an Italian conductor, cellist and composer. His early career was in Italy, where he established a reputation in Perugia and then Bologna. After 1886 he worked mostly in other countries, as principal conductor at the Royal Opera House, Covent Garden in London and at the "Old Metropolitan" Opera House in New York, and in other appointments in Madrid, Rio de Janeiro and Buenos Aires.

Mancinelli was highly regarded not only in the Italian repertory, in which he first came to prominence, but also in German and French opera. Despite his high reputation as a conductor, his compositions met with limited success, and none of them entered the regular repertoire.