Otto Bache (21 August 1839 – 28 June 1927) was a Danish Realist painter. Many of his works depict key events in Danish history.

At age eleven he received a dispensation and was admitted into the Royal Danish Academy of Fine Arts, studying under Wilhelm Marstrand, among others.^[1]

In 1866, he received the Academy's travel grant and went to Paris and later to Italy. His stay in Paris had a particularly deep impact on his work, turning it in a direction characterized by more freedom, more colour, stronger light, and broader scope.^[1] Upon his return in 1868, he was married.

He was named a Commander in the Order of the Dannebrog and later was awarded the Dannebrogordenens Hæderstegn.

He received early recognition as a portrait painter but he also showed great interest in painting animal motifs, gradually also turning to genre works and history painting.^[1]

He was the father of lawyer Niels Haagensen Bache.

• A Pack of Horses Outside an Inn
• The Conspirators Ride from Finderup After the Murder of Eric Klipping
• Danish Soldiers Return to Copenhagen in 1848
• Colonel Müller at Sankelmark Lake