Gianluigi Cornaggia Castiglioni, an Italian numismatist, was active in Milan in the first half of the twentieth century. He was closely involved with the Società Numismatica Italiana and its journal and can be found among the directors of the Rivista italiana di numismatica. He died in the early 1960’s, as  the journal's 1964 volume includes his "In memoria" notice.

His published work covered both ancient coins as well as more modern material. In 1918 he published a study of the third-century antoniniani in the hoard from Via S. Maria e Stampatori in Turin, in volume 31 of the Rivista, a paper still cited in hoard research today. He also wrote on Renaissance medals, often with Augusto Calabi, including studies of Matteo de' Pasti and anonymous Riminese medallists, a piece on a contemporary forger of ancient coins, and an article on Carlo Vicenzi. Calabi and Cornaggia's joint work of 1925 appears as a standard reference in catalogues of medals.