"Stewie Kills Lois" and "Lois Kills Stewie" are a two-part episode of the sixth season of the animated comedy series Family Guy, which was originally produced for the end of the fifth season. Respectively, both parts are the fourth and fifth episode of their season, and they premiered in the United States on Fox on November 4 and 11, 2007. In the former, housewife Lois receives cruise tickets from anthropomorphic dog Brian, and invites her husband, Peter, on the cruise with her. This upsets Stewie, and he ultimately appears to murder Lois while she is on the cruise, only to find out that she had survived the attack as the year passes. In the latter, Lois is able to expose Stewie as the villain that he is, but he soon accomplishes his dream of world domination.

"Stewie Kills Lois" was written by David A. Goodman and directed by John Holmquist, while "Lois Kills Stewie" was written by Steve Callaghan and directed by Greg Colton. Both episodes received relatively positive reviews for their combined story arc and cultural references. "Lois Kills Stewie" featured appearances by Patrick Stewart, Paula Abdul, Randy Jackson and Simon Cowell and both episodes featured cameos by various recurring voice actors for the series.