Lenk appeared as Yitzak in
Hedwig and the Angry Inch at the Broadway Theatre, Chicago, in May 2001. She performed as
Linda Lovelace in the musical
Lovelace: A Rock Musical in 2008 at the
Hayworth Theatre, Los Angeles, about which the
L. A. Weekly wrote: "As Linda, Katrina Lenk is sensational—she has a dozen nuanced smiles that range from innocent and shattered to grateful, in order to express whatever passes as kindness when, say, a male co-star (Josh Greene) promises to make their scene fun." She made her
Broadway debut in
The Miracle Worker in March 2010 as the understudy for the roles of Annie Sullivan and Kate Keller. She joined the cast of the Broadway
musical Once in May 2013, in the role of Réza, the violinist. In 2015 she appeared in the
Yale Repertory Theatre world premiere of
Indecent by
Paula Vogel. She then appeared in the 2016
Off-Broadway production at the Vineyard Theatre, followed by the Broadway production at the Cort Theatre in 2017. In her review for
Newsday, Linda Winer noted the "...dancing, singing actors as the earthy, sensual Katrina Lenk." For her performance she received the 2017
Theatre World Award Dorothy Loudon Award for Excellence. Lenk appeared on Broadway as Dina in the 2017 musical ''
The Band's Visit, for which she won the 2018 Tony Award for Best Actress in a Musical. Craig Nakano of the Los Angeles Times'' wrote: "For Lenk, the role is another turning point. After studying music and theater at Northwestern University, Lenk devoted herself to theater in California.... it’s her poignant, heart-aching turn as Dina that is poised to make her a star." She is the creator of musical persona and stage act Moxy Phinx. Lenk starred in the lead role of Bobbie, opposite
Patti LuPone as Joanne, in a gender-swapped revival of
Stephen Sondheim's
Company, which started previews on Broadway at the
Bernard B. Jacobs Theatre on March 2 and was scheduled to open on March 22, 2020, until delayed by the
COVID-19 pandemic. The production resumed previews on November 15, 2021, for an opening date of December 9, 2021. Lenk also appeared in the final season of
Ozark, playing the role of Clare. ==Theatre==