Jaques Morelenbaum (Rio de Janeiro, May 18, 1954) is a Brazilian instrumentalist, arranger, conductor, composer and music producer.

Son of conductor Henrique Morelenbaum and piano teacher Sarah Morelenbaum. Brother of Lucia Morelenbaum, clarinettist of the Brazilian Symphony Orchestra, and Eduardo Morelenbaum, conductor, arranger and instrumentalist. He is married to the singer Paula Morelenbaum.

He started his musical career as part of group A Barca do Sol, participated in the Nova Banda that performed with Antonio Carlos Jobim, acting in shows and recordings that led to the Grammy winners with the CD Antonio Brasileiro. A cellist, he studied music in Brazil and later joined the New England Conservatory of Music. He integrated the Quarteto Jobim Morelenbaum in 1995, along with Paula Morelenbaum, Paulo Jobim and Daniel Jobim with whom he toured several times to Europe, including presentation at the Expo'98 held in Lisbon, in addition to presentations at the United States and Brazil and a CD recording of Quarteto Jobim Morelenbaum.