The son of Enrico Cappelli, a popular mid-nineteenth-century theater actor from Bologna, he formed a theater company with Eleuterio Rodolfi in 1905. In 1907 he had the direction of the Teatro Stabile di Roma with Ferruccio Garavaglia. He later moved on to the companies of Italia Vitaliani, Emma Gramatica, again with Garavaglia, and to that of Ugo Farulli.

Active in silent films from 1909 to 1928 he shot almost 70 films, mostly in supporting roles, and worked for numerous production companies such as Ambrosio Film, Cines, Film d'Arte Italiana, Gloria Films, the German UFA and other minor ones. Between 1921 and 1922, he directed five films, one of which, Lo strano viaggio di Pim-Popò by the Turin-based Piemonte Film and directed together with Giovanni Casaleggio, starred his son Franco Cappelli, born of his union with actress Daisy Ferrero.