Zanetti spent his early manhood making wise investments in marine insurance, accumulating sufficient capital to support his true vocation, as a writer and artist, and as an art dealer, doing much of his business with the English aristocrats who passed through Venice on the Grand Tour.

Pierre Crozat, being in Venice in 1715, persuaded Zanetti and his protégé Rosalba Carriera to go to Paris.

Zanetti also visited London, where he purchased Jan Petersen Zoomer's three large volumes containing 428 Rembrandt etchings in outstanding impressions of the various states.

Gori's Le gemme antiche di Anton Maria Zanetti (1750), illustrated with eighty plates of engravings from his own drawings.

As a printmaker, Zanetti advanced the art of the Chiaroscuro woodcut, producing many prints after paintings by Parmigianino, Tintoretto and others.