Marie-Line Landerwyn is a Belgian voice actress born on April 3, 1970, in Brussels, Belgium. She is primarily known for her extensive work in the French dubbing of animated series and films, and her career encompasses voice acting, voice directing, adaptation, and singing. Her name also appears under the spelling Marie-Line Landerwijn or Maryline Landerwijn.

Landerwyn is perhaps most recognized for her long-standing role as the voice of Ran Mouri in the French version of the long-running anime series Detective Conan, a role she has played since the series first French dub in the mid-1990s. She has also voiced the character Mitsuhiko Tsuburaya in the same series. Her work on Detective Conan extends to its feature films; she voiced Ran Mouri and Mitsuhiko Tsuburaya in The Scarlet Bullet and Ran Mouri in The Bride of Halloween. Another prominent role in her career is Ulrich Stern in the French animated series Code Lyoko, which she voiced for all four seasons. She also voiced the character Milo du Scorpion in the film Saint Seiya: Legend of Sanctuary, as well as Shaina in Saint Seiya: The Hades Chapter - Sanctuary. Her voice work spans a wide variety of other series and films. She voiced Timmy Turner in the French dub of The Fairly OddParents and has contributed to the French versions of series such as BoJack Horseman, where she voiced multiple characters including Beatrice Horseman, as well as roles in D.Gray-Man, Mermaid Melody Pichi Pichi Pitch, Devilman Crybaby, Reideen, and My Little Pony: Friendship is Magic.

Beyond voice acting, Landerwyn has a significant career in voice directing and adaptation. She served as the art director for seasons three and four of Code Lyoko. Her direction work includes the French dubs of series such as The Amazing World of Gumball, Regular Show, Rick and Morty, Initial D, and Saiyuki. She has also been responsible for the French adaptation of numerous Pokémon films and series, including Pokémon Diamond and Pearl, Pokémon Black and White, Pokémon Sun and Moon, and several feature films from Zoroark, the Master of Illusions through Volcanion and the Mechanical Marvel. In addition to her adaptation work for the Pokémon franchise, she sang theme songs for Pokémon The Movie: White - Victini & Zekrom and for the twentieth and twenty-second seasons of the series. Her recurring collaborations in the Detective Conan franchise often involve voice actors Bruno Mullenaerts and Ioanna Gkizas.