Anna Dorothea Oscàr (1875–1915) was a Swedish opera singer. Considered to be Sweden's leading soprano of the period, she made her debut using her maiden name, Anna Thulin, at the Royal Swedish Opera as Papagena in Mozart's The Magic Flute when she was 16. Engaged by the company in 1896, she remained there for the rest of her life singing some 60 different roles in the major German, Italian, French and Swedish operas. Apart from three successful summer tours to the United States in the 1900s, she was otherwise based in Sweden. Married twice, she performed under the name Anna Hellström during her first marriage from 1900 through 1905, and after her second marriage in 1907 to the baritone Martin Oscàr, as Anna Oscàr. In 1908 she was elected a member of the Royal Swedish Academy of Music.