Born in Bari, Marcello Rosiello studied singing with Lucia and Pietro Naviglio and graduated from the Conservatorio Duni in Matera. Alongside his musical training, he also pursued academic studies, earning a degree in Biological Sciences from the University of Bari.

In the 2025/2026 season, he will perform the role of Beaupertuis in Il cappello di paglia di Firenze at the Opéra Royal de Wallonie in Liège (Belgium), Giorgio Germont in La traviata, and the leading roles in the double bill Gianni Schicchi(Puccini) and La benedizione (Carrara) at Teatro Coccia in Novara. Additionally, he will appear as Tonio in Pagliacci at Teatro Rendano in Cosenza, Bill in Rise and Fall of the City of Mahagonny at Teatro Verdi in Trieste, and will be engaged in various concerts, including an opera gala in Helsinki.

In the 2024/2025 season, he sang Malatesta (Don Pasquale) at the Opéra Royal de Wallonie in Liège, Silvio(Pagliacci) at Teatro Comunale di Bologna, Figaro (Il barbiere di Siviglia) at Teatro Lirico in Cagliari, and Ping (Turandot) at Teatro Verdi in Trieste. He also made his role debuts as Alfio in Cavalleria rusticana and Tonio in Pagliacci at Teatro Coccia in Novara, and performed as the baritone soloist in Stravinsky’s Pulcinella as part of the Festival Duni in Matera.

Highlights of the 2022/2023 season included his debut as Rodrigo in Don Carlo at the National Kaohsiung Center for the Arts (Weiwuying) in Taiwan and the Conte di Luna in Il trovatore at the Japan Opera Festival in Horyu-ji, Japan. He also performed Figaro in Il barbiere di Siviglia at the Opéra Royal de Wallonie in Liège, and Lescaut in Manon Lescaut at Teatro del Giglio in Lucca, Teatro Alighieri in Ravenna, and Teatro Pavarotti in Modena. His debut in the title role of Gianni Schicchi took place during the 2020/21 season, with performances in Ravenna, Ferrara, Lucca, and Chieti.

Notable past engagements include Figaro in Il barbiere di Siviglia, Marcello in La bohème, Germont in La traviata, Sharpless in Madama Butterfly, and Belcore at Teatro La Fenice in Venice. He has performed Carmina Burana at Teatro Massimo in Palermo, Maggio Musicale Fiorentino, and Teatro Regio in Turin, and Zurga in Les pêcheurs de perles in Trieste. At the Arena di Verona, he performed Germont in La traviata, Ping in Turandot, and Morales in Carmen. At Teatro Comunale di Bologna, he sang Marcello in La bohème and Escamillo in Carmen. Furthermore, he has interpreted Germont in La traviata across the Lombardy and Emilia-Romagna circuit, including the theaters of Reggio Emilia (Valli), Modena (Pavarotti), Como (Sociale), Brescia(Grande), Bergamo (Donizetti), Cremona (Ponchielli), and Pavia (Fraschini).