Johnny Galecki Leonard Hofstadter Actor Jim Parsons Sheldon Cooper Actor Kaley Cuoco Penny Actor Simon Helberg Howard Wolowitz Actor Kunal Nayyar Raj Koothrappali Actor Carol Ann Susi Debbie Wolowitz Guest Voice Mayim Bialik Amy Farrah Fowler Guest Star Vernee Watson Althea Guest Star Chuck Lorre Executive Producer, Writer Bill Prady Executive Producer Lee Aronsohn Writer David Goetsch Writer Steven Molaro Writer Eric Kaplan Writer Steve Holland Writer Mark Cendrowski Director