Born in Milan (Italy), completed his musical studies at Conservatorio "G. Verdi". His teachers were Luciano Chailly for the Composition, Alessandro Santinelli for the Piano, Mario Gusella for the Orchestral Conducting. He followed master-classes at the Accademia Chigiana, in Siena, and at the Accademia Nazionale di Santa Cecilia in Rome, where he achieved the final high-diploma in Orchestral Conducting under the guide of Franco Ferrara.
He was pointed out by one national competition (RAI Torino, 1981) and three international competitions for young conductors ("Premio Gui", Firenze 1982, "Premio Cantelli", Milano 1983 and "Prix Ansermet", Genève 1984). This fact allowed him to begin his work as guest conductor in many Italian and foreign chamber and symphony orchestras where, up till now, he is regularly invited (ORT – Orchestra della Toscana, Orchestra Sinfonica di Bolzano e Trento, Orchestra de “I Pomeriggi Musicali” in Milan, Orchestra dell’Arena di Verona, Orchestra della RTSVI in Lugano, Orchestra della Fondazione Toscanini in Parma, Gli Archi Italiani, etc.).
Moreover Mezzanotte Nehamas collaborated with some particular projects as "Musica nel Nostro Tempo" (Music in our time), for contemporary music, and another one dedicated to Bach's Cantatas, promoted by Piero Farulli and Scuola Normale Superiore in Pisa. He has conducted very different repertoires, making space as to his curiosities, as to his fondnesses. After the invitation of the West German Radio of Cologne (Westdeutsches-Rundfunk Köln), he has recently recorded some unpublished, or seldom listened to, symphonic pieces and film-music of Pietro Mascagni and Franco Ferrara.
Giorgio Mezzanotte is regularly also guest conductor at the Orchestra Filarmonica di Torino, Orchestra da Camera di Mantova, Orchestra Sinfonica della Valle d'Aosta, Orchestra da Camera "Il Quartettone", "Roma Sinfonietta" and at all the Italian regional orchestras (ICO). In February 2011 he has been invited by the prestigious Japanese Orchestra Ensemble Kanazawa as first Italian guest conductor. During 2012, 2013 and 2014 he has collaborated with Camerata RCO (Royal Concertgebouw Orchestra of Amsterdam), the Chamber Orchestra of Maggio Musicale Fiorentino, Thüringen Philharmonie Gotha and Symphonieorchester Volksoper Wien. He has made a CD recording of the Mass in Es D.950 of Franz Schubert, with the "Ars Cantica Choir" and the "Quartettone" chamber orchestra. This recording received very good critiques.
He collaborated with soloists as Robert Cohen, Michael Flaksmann, Bin Huang, Alexander Lonquich, Marco Rizzi, Renata Scotto, Susanna Rigacci, and many others. He also made recordings for the Italian Radio and Television Company (RAI), the West German Radio (W.D.R.- Köln), SKY Classica-Unitel.
He founded the Festival Massimo Amfiteatrof’s Ensemble and Chamber Orchestra, that he conducts in symphonic and chamber works.  In the field of his personal research on the relationship between music and depth psychology  he held conferences for the meeting “Le forme dell’immaginario”, in occasion of the  2nd  Biennale of Cremona Liuteria and for the Association “Mozart in Italia”.
At the moment, Giorgio Mezzanotte Nehamas is looking after a project to rediscover the Italian symphonic music of the end of ‘800 (such as Martucci, Sgambati) and the most important pieces of Casella and Gian Francesco Malipiero. Moreover he masters in his repertoire the principal Italian artists of the beginning of the XX century like Respighi (Symphonic poems), Rota (Symphony on a love song, soudtracks, Concerto Soirée pour piano and orchestra), Dallapiccola (Piccola Musica Notturna).