Otto Dix was born in Untermhaus, Germany, now a part of the city of Gera. In 1910, he entered the Dresden School of Arts and Crafts and supported himself as a portrait painter.

When the First World War erupted, Dix enthusiastically volunteered for the German Army. He was taken to a field artillery regiment in Dresden. In the fall of 1915 he was assigned as a non-commissioned officer of a machine-gun unit in the Western front and took part of the Battle of the Somme. He was seriously wounded several times. In 1917, his unit was transferred to the Eastern front until the end of hostilities with Russia. Back in the western front, he fought in the German Spring offensive. He earned the Iron Cross and reached the rank of vice-sergeant-major.

Dix was profoundly affected by the sights of the war. He would later tell about his recurring nightmare where he was crawling through destroyed houses. He produced a series of drawings and prints that reflected that traumatic period.

In the Weimar Republic Dix studied at the Dresden Art Academy, became a founder of the Dresden Secession, and was a contributor to the Neue Sachlichkeit exhibition in Berlin in 1925. His paintings became his expression of the bleaker side of life, especially war. He used realistic pictures of disfigured soldiers as his model. His 1923 painting The Trench, which depicted dismembered and decomposed bodies of soldiers in a trench after a battle caused such a furor that the Wallraf-Richartz Museum hid the painting behind a curtain. In 1925 the then-mayor of Cologne, Konrad Adenauer, cancelled the purchase of the painting and forced the director of the museum to resign.

Like the work of his friend and fellow veteran George Grosz, Dix's material was extremely critical of contemporary German society and often dwelled on the act of Lustmord, or sexual murder. Dix's postwar depictions of soldiers and veterans very clearly illustrates their invisibility within contemporary German society, a concept also developed in Erich Maria Remarque's All Quiet on the Western Front.

When the Nazis came to power in Germany, they regarded Dix as a degenerate artist and had him sacked from his post as an art teacher at the Dresden Academy. He later moved to Lake Constance. Dix's paintings The Trench and War cripples were exhibited in the Nazi exhibition of degenerate art, Entartete Kunst. They were later burned.

Dix was forced to join the Nazi-controlled Imperial chamber of Fine Arts in order to be able to work as an artist at all and had to promise to paint only landscapes. He still painted an occasional allegorical painting that criticized Nazi ideals. In 1939 he was arrested on a trumped-up charge of being involved in a plot against Hitler but was later released.

During World War II Dix was conscripted into the Volkssturm. He was captured by French troops at the end of the war and released in February 1946.

Dix eventually returned to Dresden. After the war most of his paintings were religious allegories or depictions of post-war suffering.

Otto Dix died in Singen, Germany, in 1969.