Carlo De Martini, son of Apulian immigrants in Lombardy shortly after the Resistance, began his musical adventure in the Stormy Six (1973-78) at age 17, graduated in violin from the Conservatorio Verdi in Milan and taught for the next 40 years at the Civica Scuola di Musica in Milan, now named after Claudio Abbado, where he created the chamber orchestra Il Quartettone (1987-2010) and the Youth Orchestra (1991), which is still active today.

He has conducted Mozart's Operas (The Magic Flute, The Clemency of Titus, and Idomeneo for the regional circuit Lombardy and recorded as a violinist, violist, and conductor some fifty pieces of vinyl and CDs, including the complete serenades by Mozart for orchestra (with original instruments, 2005, Amadeus) and Mozart's Violin Concertos, with the participation of Giuliano Carmignola (1997, Amadeus), but he has mainly devoted to chamber music: Milan Quartet (1978-1983), Johannes Trio (1981-1987), Duo with Laura Alvini (1987-1991), Quartetto Le Ricordanze (with original instruments 1992-1999), Ensemble Aglaia (1997-2004), La Gaia Scienza (original instruments,1998-2008), Classico Terzetto Italiano (since 2005).

He has collaborated extensively with Sandor Végh's "Camerata Academica Salzburg" in the 1990s and with Il Giardino Armonico (since 2008). Founding member in 1987 of the "Festival der Zukunft" in the German-speaking part of Switzerland with Gyorgy Sebok and frequent guest of "Open Chamber Music" by Sandor Végh in Cornwall, he worked for ten years inside the San Vittore prison in Milan, in the "La Nave" rehabilitation project, following the inmates' choir. In 2018 he published for the publisher Armelin an essay on the interpretation of Bach's Sonatas and Partitas for solo violin.

Since 1981 he has been teaching violin at the Civica Scuola di Musica in Milan,, where he has formed and directed since 1991 the youth orchestra dedicated to the students of the first courses. He has held campuses and summer courses for individual and orchestral training for several years.