What a Nightmare, Charlie Brown! is the 17th prime-time animated television special based on the comic strip Peanuts by Charles M. Schulz. It originally aired on Thursday, February 23, 1978, at 8:00 P.M. ET/PT on CBS. The special is unusual in that Snoopy and Charlie Brown are the only members of the Peanuts cast to appear in it. The plot is similar to that of Jack London's The Call of the Wild, and it centers on Snoopy having a nightmare about being an Arctic sled dog. This was the first special Bill Melendez directed since 1973's A Charlie Brown Thanksgiving.

In June 2010, the special debuted on DVD as part of the Peanuts 1970's Collection, Volume Two set by Warner Home Video. Before that it was released on CED format in 1983, and on VHS by Media Home Entertainment in 1985, Hi-Tops Video in 1988, and on September 6, 1995 by Paramount Home Entertainment along with It's Magic, Charlie Brown. The special occasionally saw airings on the American TV channel Nickelodeon from 1998 to 2000 as part of Nickelodeon's umbrella branding for Peanuts programming, You're on Nickelodeon, Charlie Brown!.