Theodor Albrecht Edwin Klebs (6 February 1834 – 23 October 1913) was a German-Swiss pathologist. He is mainly known for his work on infectious diseases. He is the father of Arnold Klebs.

Klebs was born in Königsberg, Province of Prussia. He studied at the University of Würzburg under Rudolf Virchow in 1855 and received his doctorate at the University of Berlin in 1858. He achieved his habilitation at the University of Königsberg the following year.

Klebs was an assistant to Virchow at the Charité in Berlin from 1861 until 1866, when he became a professor of pathology at the University of Bern in Switzerland. He married Rosa Grossenbacher, a Swiss, and also acquired Swiss citizenship. He served as a military physician for the Prussian Army in 1870 during the Franco-Prussian War; several of his ancestors had fought during the Napoleonic Wars.

Klebs taught at Würzburg from 1872–73, at Prague from 1873–82, and at Zürich from 1882–92. Because of disagreements with the rest of the faculty, the impetuous Klebs resigned from Zürich in 1893 and ran an unsuccessful private business in Karlsruhe and Strassburg in 1894.