Giovanni Gaetano Bottari (15 January 1689, Florence - 5 June 1775, Rome) was an Italian librarian and counsellor to pope Clement XII Corsini. He is the author of several treatises about art and artists. Amongst his works is Dialoghi sopra le tre Arti del Disegno, published in Lucca, 1754. In these dialogues he criticizes the role of patrons, who "understand little of art" (Dialoghi II & III).
Bottari was acquainted to Piranesi. He probably collaborated on Piranesi's answers to the letters of Pierre-Jean Mariette, and Piranesi dedicated his Antichità Romane de' Tempi della Repubblic to Bottari.