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 Jerry O'Connell Georgie Guest Star Lynn Andrews Margaret Guest Star Ellie Reed Jenna Guest Star Chuck Lorre Executive Producer Bill Prady Executive Producer Steven Molaro Executive Producer Steve Holland Writer Eric Kaplan Writer Anthony Del Broccolo Writer David Goetsch Writer Maria Ferrari Writer Jeremy Howe Writer Mark Cendrowski Director