Peter Gertner, also known as Gärtner (c. 1495 – after 1541 in Nuremberg) was a German painter.
Peter Gertner received citizenship (burgher rights, Bürgerrecht) of Nuremberg on 12 January 1521, where he presumably learned from the painter Wolf Traut.
He became known as a portrait painter and worked for Casimir, Margrave of Brandenburg-Kulmbach in 1527.
With Casimir's widow Susanna of Bavaria, after her marriage to Otto Henry, Peter went to the court of Neuburg an der Donau, where he worked as Master Peter, Court Painter (Maister Peter, Hofmaller).
His signature was his monogram pg on a gardener's spade, which is why he is sometimes referred to as "Master PG".