Haim Ernst Wertheimer (Hebrew: חיים ארנסט ורטהיימר; August 24, 1893 – March 23, 1978) was an Israeli biochemist.

Wertheimer was born in Bühl, Germany in 1893 and studied in his native town and in Baden-Baden.

He commenced studying medicine in 1912, initially in Berlin, Bonn and Kiel, before his studies were interrupted by World War I, where he served in a medical capacity in Flanders and Italy, and was awarded the Iron Cross, second class, and other decorations.

[1] In 1920–21 Wertheimer worked as a doctor at Berlin's municipal orphanage, and subsequently received a position at the Institute for Physiology, University of Halle.

In 1934 he emigrated to Mandate Palestine and accepted a job as temporary director of the Laboratory of Chemistry, at Hadassah Medical School in the Hebrew University of Jerusalem.