[2][3] Regnoli's work ranged from sword-and-sandal films, westerns, horror and sexy comedies.
[2] His final film where he was officially credited as a director was La principessa sul pisello in 1976.
[4] Regnoli did uncredited direction on the 1986 melodrama Giuro che ti amo starring Nino D'Angelo.
[4] Regnoli was also employed as the film critic for the Vatican's daily newspaper L'Osservatore Romano.
[2] Piero Regnoli's work as writer often dealt with themes of eroticism, such as in Brunello Rondi's Tecnica di un amore (1973), Roberto Bianchi Montero's Caligula's Hot Nights (1977) and Mario Bianchi's Satan's Baby Doll (1983).