Betzy Aleksandra Kjelsberg (née Børresen) (1 November 1866 – 3 October 1950) was a Norwegian women's rights activist, suffragist and a member of the feminist movement.
After her father died, the family moved to Drammen, where Betzy's mother married merchant Anton Enger.
While living there, she started her examen artium, as one of the first women in Norway to do so, but she never actually finished it due to the poor economy of her stepfather.
She served as a member of the organization together with fellow rights activists Karen Grude Koht, Fredrikke Marie Qvam, Gina Krog and Katti Anker Møller.
From 1921–1934, Kjelsberg was the Norwegian government's representative at the meetings of the International Labour Organization in Geneva.