The Big Bang Theory (TV) Cast
The cast of The Big Bang Theory. Updated on September 18, 2025.
371 actors
Johnny Galecki
as Leonard Hofstadter (279 episodes)

Johnny Galecki portrays Leonard Hofstadter, a socially inept physicist who often serves as the straight man to his friends' eccentric behaviors. Leonard is intelligent and has a somewhat low self-esteem. He develops an on-again, off-again romantic relationship with Penny throughout the series.

Jim Parsons
as Sheldon Cooper (279 episodes)

Jim Parsons plays Sheldon Cooper, a highly intelligent but socially inept physicist with obsessive-compulsive tendencies. Sheldon often struggles with social interactions and has a love for routine and order. His unique personality and quirks provide much of the show's humor.

Kaley Cuoco
as Penny (279 episodes)

Kaley Cuoco portrays Penny, a beautiful and outgoing aspiring actress who lives across the hall from Leonard and Sheldon. Penny is often the voice of reason and offers a contrasting perspective to the group's nerdy interests. Throughout the series, she forms close friendships with the main characters.

Simon Helberg
as Howard Wolowitz (279 episodes)

Simon Helberg plays Howard Wolowitz, a brilliant aerospace engineer with an overbearing and somewhat creepy personality. Howard is known for his distinctive fashion choices and his obsession with women. He is in a long-term relationship with Bernadette and together they have children.

Kunal Nayyar
as Rajesh Koothrappali (279 episodes)

Kunal Nayyar portrays Rajesh Koothrappali, an astrophysicist who initially struggles with selective mutism, making it difficult for him to talk to women. Raj eventually overcomes his condition and forms romantic relationships throughout the series. He is known for his calm and gentle demeanor.

Melissa Rauch
as Bernadette Rostenkowski (221 episodes)

Melissa Rauch plays Bernadette Rostenkowski, a microbiologist who later becomes Howard's wife. Bernadette has a high-pitched voice and a strong personality. Despite her small stature, she is not afraid to assert herself and often provides comedic moments with her feistiness.

Mayim Bialik
as Amy Farrah Fowler (217 episodes)

Mayim Bialik portrays Amy Farrah Fowler, a neurobiologist who becomes Sheldon's love interest. Amy is highly intelligent, socially awkward, and shares many quirks with Sheldon, making her a good match for him. Throughout the series, her character undergoes significant personal growth.

Kevin Sussman
as Stuart Bloom (84 episodes)
Travis Schuldt
as Eric (2 episodes)

Travis Schuldt guest stars as Eric, Penny's ex-boyfriend. Eric appears in a few episodes, providing some romantic tension and comedic moments with his interactions with the main characters.

Octavia Spencer
as Octavia (1 episode)
Michael Trucco
as David Underhill (2 episodes)
Summer Glau
as Self (1 episode)
Jodi Lyn O'Keefe
as Mikayla (2 episodes)
Lewis Black
as Professor Crawley (2 episodes)
Elizabeth Bogush
as Catherine Millstone (1 episode)
Yeardley Smith
as Sandy (2 episodes)
Julio Oscar Mechoso
as Officer Hackett (1 episode)
Judy Greer
as Elizabeth Plimpton (1 episode)
Steve Wozniak
as Self (1 episode)
George Takei
as Self (1 episode)
Eliza Dushku
as Angela Page (2 episodes)
Rick Fox
as Glenn (2 episodes)
Jessica Walter
as Mrs. Latham (2 episodes)
Kimberly Kevon Williams
as Vicki (1 episode)
Andrew W. Walker
as Mike (1 episode)
Emma Degerstedt
as Emma (1 episode)
Peter Onorati
as Angelo (1 episode)
Brooke D'Orsay
as Christy Vanderbel (1 episode)
Brian Patrick Wade
as Kurt (3 episodes)
Michael Hyatt
as Charlotte (2 episodes)
Will Deutsch
as Jeremy (2 episodes)
Valerie Azlynn
as Alicia (2 episodes)
Oliver Muirhead
as Professor Laughlin (1 episode)
Danica McKellar
as Abby (1 episode)
Erin Allin O'Reilly
as Cheryl (2 episodes)
James Hong
as Chen (2 episodes)
Sherry Weston
as Dance Instructor (1 episode)
Joel Brooks
as Professor Goldfarb (1 episode)
Blake Berris
as Kevin (2 episodes)
Courtney Ford
as Alice (2 episodes)
Allen Nabors
as Doug (1 episode)
Rachel Cannon
as Patty (1 episode)
Billy Bob Thornton
as Oliver Lorvis (1 episode)
Stephen Root
as Dan (2 episodes)
Kara Luiz
as Jeanie (1 episode)
James Earl Jones
as Self (1 episode)
Carrie Fisher
as Self (1 episode)
DJ Qualls
as Toby Loobenfeld (1 episode)
LeVar Burton
as LeVar Burton (3 episodes)
Sarayu Blue
as Lalita Gupta (1 episode)
Dakin Matthews
as Santa Claus (2 episodes)
Michael Reetz
as Photographer (1 episode)
Noel De Souza
as Older Indian Man (1 episode)
Nathan Fillion
as Nathan Fillion (1 episode)
Angela Relucio
as Hostess (1 episode)
Stephanie Escajeda
as Cindy (1 episode)
Max Adler
as Zombie (1 episode)
Tate Ellington
as Mitchell (1 episode)
Michael Dempsey
as Security Guard (1 episode)
Mark Barrett
as Security Guard #2 (voice) (1 episode)
Matt Bennett
as Josh Wolowitz (1 episode)
Jim Meskimen
as Doctor (voice) (1 episode)
Rena Strober
as Caller (voice) (1 episode)
Sara Erikson
as Gwen (1 episode)
Kelli Goss
as Chelsea (1 episode)
Phoebe Neidhardt
as Casting Assistant (1 episode)
Jeff Jingle
as Alien (voice) (1 episode)
Mark Maitre
as Alien #2 (voice) (1 episode)
Max Mittelman
as Tech Support (voice) (1 episode)
Katherine Von Till
as Tech Support Recording (voice) (1 episode)
Louise Claps
as Receptionist (1 episode)
Melissa Tang
as Mandy Chao (1 episode)
Craig Welzbacher
as Candidate #1 (1 episode)
Kurt Koehler
as Candidate #2 (1 episode)
Arshad Aslam
as Candidate #3 (1 episode)
Megan Heyn
as Natalie (1 episode)
Patrika Darbo
as Grace (1 episode)
Rebecca Ann Johnson
as Attractive Red Head (1 episode)
Michael Rapaport
as Kenny Fitzgerald (1 episode)
Elena Campbell-Martinez
as Maria (2 episodes)
Troy Winbush
as Paramedic (1 episode)
Sophie Oda
as Grace (1 episode)
Alex Ball
as Waiter (2 episodes)
Aaron Takahashi
as Scientist (1 episode)
Barak Hardley
as Pizza Delivery Guy (1 episode)
Christine Corpuz
as Woman (1 episode)
Todd Eric Andrews
as Dr. Gunderson (1 episode)
Ayumi Iizuka
as Scientist (1 episode)
Adam Nimoy
as Self (1 episode)
Elon Musk
as Elon Musk (1 episode)
Wayne Wilderson
as Travis (1 episode)
Yoshi Barrigas
as Trent Monaco (1 episode)
Becky O'Donohue
as Siri (voice) (1 episode)
Jane Kaczmarek
as Dr. Gallow (1 episode)
June Squibb
as Connie Tucker (1 episode)
Alessandra Torresani
as Claire (5 episodes)
Adam West
as Self (1 episode)
Creagen Dow
as Glenn the Maitre D' (1 episode)
Shane Blades
as Customer (1 episode)
Bruce Holman
as Airport Pedestrian (1 episode)
For the best insights and data about the TV show The Big Bang Theory, visit our main The Big Bang Theory page.