He studied medicine and the natural sciences first in Berlin and later in Zürich under Johann Lukas Schönlein.

For the next year and a half he studied in Paris, particularly under Baron Guillaume Dupuytren and Pierre Charles Alexandre Louis.

From 1842 to 1845 he worked mainly in comparative anatomy, which had interested him during his travels as a student on the coast of Normandy and the Channel Islands with Charles-Philippe Robin.

After a stay in Berlin during the winter of 1845–1846 Lebert settled in Paris, where he devoted his efforts to both his practice and scientific work.

In 1853 he accepted an invitation to become professor of clinical medicine in Zürich, and six years later he moved on to Breslau, where he held the same job.