Nikolaos Gyzis (Greek: Νικόλαος Γύζης [niˈko.la.os ˈʝi.zis]; German: Nikolaus Gysis; 1 March 1842 – 4 January 1901) is considered one of Greece's most important 19th century painters.

In 1865, having won a scholarship, he went to continue his studies at the Academy of Fine Arts, Munich, where he settled for the rest of his life.

He was very soon incorporated into the German pictorial climate, and became one of its most characteristic representatives of the Greek artistic movement of the Munich School.

From 1886 onward he was professor at the Academy of Fine Arts, Munich, and gradually turned from the detailed realistic depictions towards compositions of a singularly impressionistic character.

His students included Jan Vochoc, Ernst Oppler, Fritz Osswald, Anna May-Rychter,[1] and Stefan Popescu (Romanian painter).