Ernst Karl Eugen Koerner (3 November 1846, Stibbe near Marienwerder – 30 July 1927, Berlin) was a German landscape painter.
In 1861, while still attending the public schools, he began working in the studios of Hermann Eschke, where he received most of his artistic education.
He spent most of the two following decades travelling; to the North Sea, the Baltics, the Harz Mountains, France, England, Italy, Scotland and Spain.
They had one daughter and three sons, including the jurist, Bernhard Koerner [de], who later became a prominent Anti-Semite.
Koerner became known above all for his pictures of Egypt, in which he depicted ancient Egyptian architecture, sometimes associated with blood-red sunsets.