The Big Bang Theory season 4

The Big Bang Theory
Season 4
DVD cover art
Starring	Johnny Galecki Jim Parsons Kaley Cuoco Simon Helberg Kunal Nayyar Melissa Rauch Mayim Bialik
No. of episodes	24
Release
Original network	CBS
Original release	September 23, 2010 (2010-09-23) – May 19, 2011 (2011-05-19)
Season chronology
← Previous Season 3 Next → Season 5
List of episodes

The fourth season of the American television sitcom The Big Bang Theory aired on CBS from September 23, 2010 to May 19, 2011.^[1] Melissa Rauch and Mayim Bialik auditioned and were promoted to the main cast during this season as Dr. Bernadette Rostenkowski and Dr. Amy Farrah Fowler respectively.

Johnny Galecki received a nomination for the Primetime Emmy Award for Outstanding Lead Actor in a Comedy Series at the 63rd Primetime Emmy Awards for the episode "The Benefactor Factor". Jim Parsons won the same award for the episode "The Agreement Dissection".