Ardoino da Piacenza (died 21 January 1183) was an Italian cardinal. His first name is listed also as Arduino.
He was archdeacon of the cathedral chapter of Piacenza and member of the Order of Canons Regular di San Frediano di Lucca. Pope Alexander III created him Cardinal in the consistory celebrated in Frascati in 1178. Between 4 July and 6 September 1178 he signed a papal bull as Cardinal-Deacon of S. Maria in Via Lata, but shortly thereafter he was promoted to the rank of Cardinal-Priest of Santa Croce in Gerusalemme; as such, he signed the bulls from 1 October 1178 until 8 January 1183. He participated in the papal election, 1181, which elected Pope Lucius III. An opuscle titled De Deo immortali is sometimes misattributed to Arduin, but this is the result of a confusion with the work of Hugo Etherianus.[1]