Melanie Jayne Lynskey (born May 16, 1977) is a New Zealand actress. Known for her portrayals of complex women and her command of American dialects, she works predominantly in independent films. Lynskey made her film debut at age 17 portraying Pauline Parker in Heavenly Creatures (1994). She went on to establish herself as a character actress through supporting parts in Ever After (1998); But I'm a Cheerleader (1999); Coyote Ugly (2000); Sweet Home Alabama (2002); Shattered Glass (2003); Flags of Our Fathers (2006); Away We Go; Up in the Air; The Informant! (all 2009); Win Win (2011); The Perks of Being a Wallflower (2012); and Don't Look Up (2021). Her starring role in Hello I Must Be Going (2012) proved to be a turning point in Lynskey's career, with subsequent lead parts in Happy Christmas (2014), The Intervention (2016), and I Don't Feel at Home in This World Anymore (2017) highlighting her as a prominent figure in independent cinema.

On television, Lynskey played Rose in Two and a Half Men (2003-2015), Shauna in Yellowjackets (2021-2026) and Kathleen in The Last of Us (2023).

Lynskey is the recipient of two Critics' Choice Awards, a HCA Award, a Gracie, a New Zealand Film Award, a Hollywood Film Award, and a Sundance Special Jury Award, as well as Gotham, Satellite, Saturn, Golden Nymph, Independent Spirit, Screen Actors Guild, and Primetime Emmy Award nominations.