The actress will make a cameo as Dr Allison Cameron in the medical drama's last episode, TVLine confirms.
Olivia Wilde (Thirteen), Kal Penn (Kutner) and Amber Tamblyn (Martha Masters) will also appear in the episode, titled 'Everybody Dies'.
Morrison - who currently stars in ABC's Once Upon a Time - previously indicated that she would not appear in the episode.
"No-one's contacted me [about returning], and we're way too close for it to even be a possibility," she said in March.
The Cameron character last appeared in sixth season episode 'Lockdown' to finalise her divorce from Chase (Jesse Spencer).
Last year, Morrison told Digital Spy that she would "love" to return to House for a guest appearance.
"I love Cameron and I'll always have an affection for [that character]," she said. "So if I were given the opportunity to [come back], of course I would."
The House series finale airs on Fox on Monday, May 21.
> House: Hugh Laurie, Omar Epps, David Shore tease series finale
Watch Jennifer Morrison discuss a possible House return with Digital Spy in 2011 below: