Moss, 48, will reprise her role as the cunning New York lawyer Jeri Hogarth to provide some much-needed help to Danny Rand (Finn Jones) when he returns to town, reported Digital Spy.
Marvel Television boss Jeph Loeb said, "Carrie-Anne has fast become a fan-favourite part of our street level saga, and we share our viewers' excitement in bringing her into Marvel's Iron Fist.
"As Marvel fans know, Hogarth in the comics plays a critical role in the life of Danny Rand so it seems only fitting that Carrie-Anne join in."
"I'm very happy to have the opportunity to bring Carrie-Ann Moss as Jeri Hogarth into Marvel's Iron Fist."
"Iron Fist" is expected to premiere on Netflix next year.