Johnny Galecki Leonard Hofstadter Actor Jim Parsons Sheldon Cooper Actor Kaley Cuoco Penny Actor Simon Helberg Howard Wolowitz Actor Kunal Nayyar Raj Koothrappali Actor Mayim Bialik Amy Farrah Fowler Actor Melissa Rauch Bernadette Rostenkowski Actor Bob Newhart Arthur Jeffries Guest Star Wil Wheaton Himself Guest Star Pamela Adlon Halley Wolowitz Guest Voice Chuck Lorre Executive Producer Bill Prady Executive Producer Steven Molaro Executive Producer, Writer David Goetsch Writer Steve Holland Writer Andrew Gordon Writer Jeremy Howe Writer Alex Yonks Writer Mark Cendrowski Director