Claudio Cassinelli was born in 1938 in Bologna. He made his cinematic debut in 1967 with Marco Bellocchio's La Cina è vicina, in parallel with some theatrical experiences alongside Gabriele Lavia and Giulio Bosetti in an edition of Goldoni's Il Bugiardo.
In 1969 it was the turn of the Italian-Bulgarian co-production Galileo by Liliana Cavani, and subsequently, in the two-year period '70-'71, of some television works: Passato remoto by M. Magri and a part in the first episode of the drama A come Andromeda by Vittorio Cottafavi. In 1973 he took part in Allonsanfan by the Taviani brothers, followed by La prima volta sull'erba (1974) by G. Calderone, candidate for the Silver Bear at the Berlin Film Festival. We then see him produce himself in a gallery of courageous and atypical Inspectors, from Luciano Ercoli's La polizia ha le mani legate, continuing with Massimo Dallamano's La polizia chiede aiuto (1974), Morte sospetta di una minorenne (1975) by Sergio Martino, Milano violenta (1976) by Mario Caiano, Il trucido e lo sbirro (1976) by Umberto Lenzi. Meanwhile he also worked in Il sorriso del Grande Tentatore (1974) by Damiano Damiani, La nottata (1974) by Tonino Cervi, Flavia, La Monaca Musulmana by Gianfranco Mingozzi − director with whom he will also work in the TV film Gli ultimi tre giorni (1978), and in television special Bologna - Fantasia, ma non troppo, per violino).
After a cameo in Nina (1976) by Vincente Minnelli, a little lucky Diamanti sporchi di sangue (1977) by Fernando di Leo and the television drama L'Inseguitore by M. Foglietti, he returns to the limelight with the adventurous triptych by Martino: La montagna del dio cannibale (1978), L'isola degli uomini pesce (1979) and Il fiume del grande caimano (1979): films with which he obtained a certain notoriety also abroad. Meanwhile he plays the measured Jesus Christ in Il ladrone (1979) by Pasquale Festa Campanile, the silent extra in the Anglo-Libyan production Lion of the Desert (1981) by Moutapha Akkad and participates in Francesco Laudadio's debut, Grog (1982).
While the eighties turned to the decline of genres, between thrillers and action films produced with very modest budgets, the actor maintained an incomparable professionalism. It can be found in the Giallo Assassinio al cimitero etrusco (1982) by Martino and Murderock - uccide a passo di danza (1984) by Lucio Fulci − with whom he will will cooperate again for the futuristic I guerrieri dell'anno 2072 (1984), in the fantapeplum diptych by Luigi Cozzi, Hercules (1983) and Le avventure dell'incredibile Ercole (1985), in the glossy soft-erotic Roma dalla finestra (Si vede) by the Japanese Masuo Ikeda. On television he appears in Fosca by Enzo Muzii, Un caso di incoscienza by Emidio Greco, I figli del vento by Doria.
His last interpretation coincides dramatically with his premature death, which occurred on July 12, 1985 on the set of the Martino's film Vendetta dal futuro (1986): during the filming he lost his life following a helicopter accident, in Page (Arizona).
- La polizia chiede aiuto (1974) .... Inspector Silvestri