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 Christine Baranski Dr. Beverly Hofstadter Guest Star Stacey Travis Sandy Guest Star Chuck Lorre Executive Producer, Writer Bill Prady Executive Producer, Writer Eric Kaplan Writer Maria Ferrari Writer Anthony Del Broccolo Writer Steven Molaro Writer