Anja Nissen (born 6 November 1995), sometimes known as simply Anja, is a Danish-Australian singer. She was the winner of the third season of The Voice Australia. Following her win, Nissen was signed to Universal Music Group and lists her influences as Celine Dion, Mariah Carey, Whitney Houston, Christina Aguilera, Toni Braxton and Stevie Wonder. In 2015, Nissen was the support act for Olly Murs on his Australian Never Been Better tour.

In 2016, Nissen competed in Dansk Melodi Grand Prix 2016, Denmark's national final for the Eurovision Song Contest, performing the song "Never Alone". She came in second place with 36% of the vote. In 2017, Nissen competed in Dansk Melodi Grand Prix 2017 with the song "Where I Am", which she co-wrote. Anja went on to win and represented Denmark in the Eurovision Song Contest 2017, where she finished 20th in the final.

Nissen has been an Australia Day ambassador, and performed at the Australia Day Event in Northern Territory. Nissen performed at the 2014 Carols by Candlelight in Melbourne, Australia. Nissen was also the face of Lyla & Co.