Johnny Galecki plays Leonard Hofstadter, Jim Parsons plays Sheldon Cooper, and Kaley Cuoco plays Penny in The Big Bang Theory.
Main cast
- Leonard HofstadterJohnny GaleckiSeasons 1–12Main
- Sheldon CooperJim ParsonsSeasons 1–12Main
- Penny / Penny HofstadterKaley CuocoSeasons 1–12Main
- Howard WolowitzSimon HelbergSeasons 1–12Main
- Raj KoothrappaliKunal NayyarSeasons 1–12Main
- Bernadette RostenkowskiMelissa RauchSeasons 3–12Main
- Amy Farrah FowlerMayim BialikSeasons 4–12Main
Supporting cast
- Stuart BloomKevin SussmanSeasons 3–12Supp
- Debbie WolowitzCarol Ann SusiSeasons 1–11Supp
- Barry KripkeJohn Ross BowieSeasons 3–12Supp
- Emily SweeneyLaura SpencerSeasons 8–10Supp
- Wil WheatonWil WheatonSeasons 3–12Supp
- Dr. V. M. KoothrappaliBrian GeorgeSeasons 1–12Supp
- Dr. Beverly HofstadterChristine BaranskiSeasons 3–12Supp
- Bert KibblerBrian PosehnSeasons 7–12Supp
- Mary CooperLaurie MetcalfSeasons 1–11Supp
- Captain SweatpantsIan Scott RudolphSeasons 3–7Supp
- President SiebertJoshua MalinaSeasons 5–12Supp
- Priya KoothrappaliAarti MannSeasons 3–4Supp
- Zack JohnsonBrian Thomas SmithSeasons 4–12Supp
- Mrs. KoothrappaliAlice AmterSeasons 1–9Supp
- Leslie WinkleSara GilbertSeasons 1–9Supp
- AnuRati GuptaSeasons 12Supp
- LucyKate MicucciSeasons 6–10Supp
- DeniseLauren LapkusSeasons 12Supp
Guest & voice
- Stephen HawkingStephen HawkingSeasons 6–11Guest
- Mrs. FowlerKathy BatesSeasons 12Guest
- Dr. PembertonSean AstinSeasons 12Guest
- WyattKeith CarradineSeasons 12Guest
- Mr. FowlerTellerSeasons 12Guest
- Dr. CampbellKal PennSeasons 12Guest
- MarissaLindsey KraftSeasons 12Guest
- Dr. GraybelDavid TheuneSeasons 12Guest
- Halley WolowitzPamela AdlonSeasons 10–12Voice
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About this cast
The Big Bang Theory is a CBS sitcom (2007–2019) about physicists and their friends. The lead cast includes Johnny Galecki, Jim Parsons, Kaley Cuoco, Simon Helberg, Kunal Nayyar, Melissa Rauch, and Mayim Bialik.
Cast FAQs
Who plays Penny in The Big Bang Theory?
Kaley Cuoco plays Penny, later Penny Hofstadter.
Who plays Sheldon Cooper in The Big Bang Theory?
Jim Parsons plays Sheldon Cooper.
Who plays Raj Koothrappali's girlfriend in The Big Bang Theory?
Raj's girlfriends include Emily (Laura Spencer), Lucy (Kate Micucci), and Anu (Rati Gupta).
How many cast members are in The Big Bang Theory?
The series has 34 cast members, including 7 lead actors.
Sources: IMDb · IMDb · Wikipedia · Rotten Tomatoes · facebook.com · Updated June 2026
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