Bill Prady (born June 7, 1960) is a television writer and producer who has worked on American sitcoms and variety programs, including Married... with Children, Dream On, Star Trek: Voyager, Dharma & Greg, and Gilmore Girls and co-created The Big Bang Theory.

He began his writing career at Jim Henson's Muppets. During his tenure at The Muppets, he was visually caricatured as the puppet "Chip" (The Jim Henson Hour). In 1991, Prady was nominated for an Emmy award for co-writing the posthumous tribute to Jim Henson entitled ("The Muppets Celebrate Jim Henson").

He wrote the Disney theme park attractions Muppet*Vision 3D and Honey, I Shrunk the Audience.

He is currently the executive producer and co-creator of the CBS sitcom The Big Bang Theory.

Prady is one of a number of graduates of the Cranbrook Schools in Bloomfield Hills, Michigan currently working in entertainment (others include actors Selma Blair and Douglas Sills, writer Todd A. Kessler and former ABC president Stuart Bloomberg). In 2009, he was presented with the schools' Distinguished Alumni award. He attended Wayne State University in Detroit, Michigan.

In 2003, he was one of 135 candidates who ran for California governor in the 2003 California gubernatorial recall election, receiving 474 votes.

Prady's "nerd cred" is often attributed to his having been a Z80 programmer at The Small Computer Company.

In 2010, Prady was given honorary membership in the Royal Canadian Institute for the Advancement of Science.

In 2013, Prady was awarded NASA's Exceptional Public Achievement Medal.