Þorbjörg Sveinsdóttir (1827 – 1903) was an Icelandic midwife and feminist, particularly known for her work for women's right to education.
She never married, but became the foster mother of her orphaned niece, the writer and feminist Ólafía Jóhannsdóttir.
In 1894, she founded a committee to work for the establishment of a university open to women.
She was one of the co-founders of the women's organization Hið íslenska kvenfélag.
In 1897, she was elected the second president of the Hið íslenska kvenfélag after Sigþrúður Friðriksdóttir.