Johnny Galecki Leonard Hofstadter Actor Jim Parsons Sheldon Cooper Actor Kaley Cuoco Penny Actor Simon Helberg Howard Wolowitz Actor Kunal Nayyar Raj Koothrappali Actor Melissa Rauch Bernadette Rostenkowski Guest Star Mayim Bialik Amy Farrah Fowler Guest Star Carol Ann Susi Debbie Wolowitz Guest Voice Aarti Mann Priya Koothrappali Guest Star Chuck Lorre Executive Producer, Writer Bill Prady Executive Producer, Writer Lee Aronsohn Writer David Goetsch Writer Steven Molaro Writer Jim Reynolds Writer Mark Cendrowski Director