Roberto Bellatalla was born in Pisa on October 25, 1954, and emerged as a double bassist in the Italian jazz scene in the first half of the 1970s. His first documented recordings come from Milan's free-jazz circle: in 1975 he is the bassist on the Quartetto Di Guido Mazzon's Ecologia, alongside Guido Mazzon (trumpet), Edoardo Ricci (alto saxophone) and Tony Rusconi (drums), and on Mazzon's own trio record Ed Ora Parliamo Di Libertà the same year. In 1976 he recorded Concerto Della Statale, a trio with Mario Schiano (alto and soprano saxophone) and the drummer Lino Liguori, and joined the eleven-piece Gaetano Liguori Collective Orchestra, led by pianist Gaetano Liguori, on a session that also carried Massimo Urbani on alto saxophone and Danilo Terenzi on trombone.

He then left Italy for Amsterdam for about two years, playing in Tristan Honsinger's quartet alongside the trombonist Radu Malfatti and the reedman Sean Bergin, and working in free improvisation with the drummer Han Bennink. Back in Rome in 1978, he took part in the Laboratorio Della Quercia, a large-cast improvising workshop recorded live over two nights that July at the "Quercia del Tasso" and issued as an LP the following year; Discogs credits him on bass and cello on the same release as Massimo Urbani, Danilo Terenzi, Enrico Rava, Steve Lacy, Roswell Rudd and Kenny Wheeler, among some two dozen musicians; the release does not itemize which of its eight pieces each player appears on, so the precise lineup on any one track is not confirmed. Later in 1978 he moved to London, where he would be based for the next quarter-century.

In London he worked with the drummer Ken Hyder and the South African altoist Dudu Pukwana, and formed a trio of double basses with Marcio Mattos and Paul Rogers. In 1982 the South African drummer Louis Moholo invited him into Viva La Black; Bellatalla stayed with the group through its 1988 debut LP and its 1993 Freedom Tour of South Africa, documented on Freedom Tour Live In South Afrika 1993 (issued 1994), recorded in the months after Nelson Mandela's release. In 1983 he joined Dreamtime, the sextet led by trombonist Nick Evans with trumpeter Jim Dvorak, a partnership that produced records into the mid-2000s, including the archival Cathanger '86 and Double Trouble (2010), the latter with the saxophonist Paul Dunmall and pianist Keith Tippett. Through the 1990s he also recorded with the John Law Quartet (1992), the Archangelsk saxophonist Vladimir Rezitsky (1994), and, in 1998, led his own quartet on Borrowed Time, with Claude Deppa (trumpet), Jason Yarde (alto saxophone) and Brian Abrahams (drums); that year he also joined Elton Dean's Newsense and recorded Dean's Headless Quartet and the trio session Into The Nieríka, co-composed with Dean and the drummer Mark Sanders. In 2001 he recorded Kunikazu with the guitarist Philip Gibbs, Keith Tippett, Paul Dunmall and the drummer Peter Fairclough, and played double bass on Robert Mitchell's Voyager.

From January 2004 he lived in Rome, working mainly with the guitarist and electronics player Mike Cooper, the drummers Fabrizio Spera and Michele Rabbia, and the saxophonist Sandro Satta, while continuing to return to Britain for projects such as the Paul Dunmall Sextet's Shooters Hill (2004). He also toured Italy in the Canto Generale project reuniting him with Louis Moholo and the trumpeter Pino Minafra, later documented as Rebel Flames (2015). 2006 was an especially active year based from Rome: he recorded the trio record Bows' Wind with Giovanni Maier and Michele Rabbia, Music Of The Angels with Michele Rabbia and the saxophonist Pasquale Innarella, Oidé with the trumpeter Angelo Olivieri, the duo improvisation Scatole Sonore and "Friendly" Fire with the pianist Gabriele Meirano and Jim Dvorak. The same year, Twister reissued a 1976 Penne Festival recording and the 1988 Effetti Larsen concert under the group name Unità Musicale, reuniting him with Guido Mazzon, Mario Schiano and Gaetano Liguori.

His later recordings include Re-Union (2011), a live trio with Sandro Satta and Fabrizio Spera; Aura Via Appia (2017) with the Biggi Vinkeloe Band; Alcheringa (2018) with the Rome-based trio Primitive Field; A String Of Curses (2019) with the guitarist Michel Kristof; and Live At Maison Makutsu (2021), a duo with the violinist Emanuele Parrini, with whom he had also recorded as part of Dinamitri Jazz Folklore on Vita Nova (2000). Oreste In Giardino (2022), with the vocalist Michiko Hirayama and the composer Luca Miti, and continued work with Paul Dunmall, including the 2025 Jazz Suite Outcome Of Choice and a 2023 concert released as A Celebration Of Keith Tippett, carry his discography into its sixth decade. Alongside performing, he has taught through seminars in London schools and music-therapy settings, and in Rome through Mus-e, the arts-education program founded by Yehudi Menuhin.

Bellatalla's catalogue sits almost entirely inside free jazz and free improvisation: Discogs tags the large majority of his more than sixty credited releases Jazz, with Free Jazz, Free Improvisation and Contemporary Jazz as the dominant styles, from his first Milan sessions in 1975 through his most recent Paul Dunmall record in 2025. He has worked as often as a duo and trio partner as a bandleader, pairing with a single horn or voice (the violinist Emanuele Parrini, the trumpeter Jim Dvorak, the vocalist Michiko Hirayama) as readily as inside larger ensembles such as the Gaetano Liguori Collective Orchestra or Louis Moholo's Viva La Black. A member of a trio of double basses with Marcio Mattos and Paul Rogers, he also doubles on cello, credited on the 1979 Laboratorio Della Quercia session alongside dedicated cellists Irene Aebi and Kent Carter. His career threads two improvising scenes together: the Milan-centred Italian free jazz circle he started in, built around Guido Mazzon, Mario Schiano and Gaetano Liguori, and the London free-improvisation and South African exile-jazz scene he spent a quarter-century inside, anchored by Louis Moholo, Keith Tippett, Elton Dean and Paul Dunmall; his return to Rome in 2004 brought the two together, reuniting him on record with his original Milan circle while he kept recording with his British partners.