Magical Girl Lyrical Nanoha StrikerS is the third season of the Magical Girl Lyrical Nanoha series. This season aired shortly after the promotional event "Lyrical Party III" on April 1, 2007. The series focuses more on team-based battles and bureaucracy rather than individual rivalry and school life, due to the change in character dynamics. The name StrikerS refers to an SS rank given to top mages, much like how A's refers to A rank mages. A special sound stage, under the name of StrikerS Sound stage X was released on October 29, 2008. A manga adaptation, which explored storylines outside of the anime series, ran in Megami Magazine from November 2006 to February 2008.

Magical Girl Lyrical Nanoha is a Japanese anime television series directed by Akiyuki Shinbo, with screenplay written by Masaki Tsuzuki and produced by Seven Arcs. It forms part of the Magical Girl Lyrical Nanoha series. The Japanese Association of Independent Television Stations broadcast 13 episodes between October and December 2004. The series is a spin-off of the Triangle Heart series and its story follows a girl named Nanoha Takamachi who decides to help a young mage named Yūno to recover a set of 21 artifacts named the "Jewel Seeds".