The tenth season of the American fictional drama television series ER first aired on September 25, 2003, and concluded on May 13, 2004.

The aftermath of Kovač and Carter's mission in Africa becomes a key story throughout the season, a Thanksgiving tragedy sees the end of Romano, Lewis copes with an unexpected pregnancy, Pratt's professionalism is tested again by his colleagues, Gallant is deployed to Iraq and Chen and Weaver both deal with personal losses.

Meanwhile, a new medical student, Neela Rasgotra, causes a stir when she unexpectedly helps a patient - and angers Chen as Pratt flirts with her.

Lewis fears for a distraught architect, Ben Hollander (Bob Newhart), whose degenerating eyesight makes him despondent.

Morris is left greatly overwhelmed by the chaos and grisly conditions of life in the ER, especially a case involving an injured child and his desperate, alcoholic mother.

Lewis suffers labor pains and is confined to bed rest, while tension remains between Gallant and Neela as an investigation begins into the suspicious death.