Melanie Jayne Lynskey (born 16 May 1977) is a New Zealand actress. She rose to prominence for her portrayal of Pauline Parker in Heavenly Creatures (1994), which was followed by supporting roles in Ever After (1998), Coyote Ugly (2000), Sweet Home Alabama (2002), and Shattered Glass (2003). Subsequent film parts include Flags of Our Fathers (2006), Away We Go, Up in the Air, The Informant! (all 2009), Win Win (2011), and The Perks of Being a Wallflower (2012). Lynskey transitioned into leading roles with the film Hello I Must Be Going (2012). She has since starred in Happy Christmas (2014), The Intervention (2016), and I Don't Feel at Home in This World Anymore (2017).

On television, Lynskey's best known role is that of Rose on the CBS sitcom Two and a Half Men (2003–15). She also appeared as Michelle Pierson on the HBO series Togetherness (2015–16), for which she received a nomination for the Critics' Choice Television Award for Best Supporting Actress in a Comedy Series.