Betty Natalie Boije af Gennäs (14 February 1822 - 14 November 1854), was a Finnish (originally Swedish) opera and concert singer (contralto) and composer.
She made a successful tour as a concert singer in Turku, Helsinki, Reval and Saint Petersburg.
In 1853-54, she toured as a concert singer with her spouse and her sister in Great Britain and the United States.
Although Betty Boije's father was indeed a nobleman, he was not rich, and her sister also supported herself as an artist (in her case a pianist).
Betty Boije's widower Isidor Dannström, in his late biography over her, claimed she had never acted on stage and merely performed as a concert singer.