They finally learn each other’s real identities for good in Season 5, Episode 26, often referred to as “The Final Day – Part 2,” when Marinette (Ladybug) reveals herself to Adrien (Cat Noir) and the truth sticks instead of being erased or undone like in earlier timelines and specials.

Quick Scoop: Identity Reveal

  • The show teases the reveal many times with “almost” moments, memory wipes, and alternate timelines where one or both briefly find out but then forget or the timeline is reset.
  • The permanent mutual reveal happens at the very end of Season 5, Episode 26 (“The Final Day – Part 2”), where Marinette openly unmasks as Ladybug to Adrien, confirming what viewers have waited for since Season 1.
  • Earlier storylines and specials may show temporary or alternate-reality reveals, but these do not last in the main continuity, which is why fans point to the Season 5 finale as the real answer to “when do Ladybug and Cat Noir find out who they are.”

In other words: they only truly, lastingly find out who the other is at the very end of Season 5, after years of fake-outs and near-reveals.

TL;DR: Ladybug and Cat Noir learn each other’s true identities for real (no reset, no memory wipe) in Season 5, Episode 26, “The Final Day – Part 2.”

Information gathered from public forums or data available on the internet and portrayed here.