Dionys Ganter was a German painter.

Dionys Ganter was one of eleven children of the blacksmith Andreas Ganter and his wife Rosina. His younger brother was the future innkeeper and painter Nikolaus Ganter (1809–1886).

He was artistically talented even as a child and initially worked as a clock and sign painter. In 1821 he went to Vienna, where he enrolled at the Academy of Fine Arts, first in the elementary drawing school, and then in 1823/24 and from 1826 to 1829 in the class for history painting. In Vienna he got to know the Nazarenes and worked as a portrait painter. He then returned to his homeland and married Magdalena Scherzinger from Rötenbach in 1837, where he initially also lived after the wedding.

During his time in the Black Forest, he mainly painted wealthy farmers and bourgeoisie, as well as views. During his time in Freiburg, he mainly painted religious motifs and altarpieces.