Beata Oxenstierna (1591 in Reval Castle – 16 March 1652), was a Swedish noblewoman and courtier. She served as överhovmästarinna to queen Christina of Sweden from 1639 to 1647.
Beata Oxenstierna was born to Baron Erik Gabrielsson Oxenstierna (1540s-1594) and Bengta Gera. Her father had been a courtier to Princess Cecilia Vasa of Sweden, and governor in Swedish Livonia, and she was born in Reval in Livonia during his tenure as governor there. She served as maid of honor to the queen of Sweden, Christina of Holstein-Gottorp, in 1610-1613. In 1613, she married Erik Göransson Ulfsparre af Broxvik (1577-1631), but as was the custom at the Swedish nobility up until the late 18th century, she kept her name even after her marriage. Her spouse served as governor in Stegeborg 1615-18, Norrköping 1618-21, Kronoberg 1621-26, and Östergötland 1627-1631; Beata Oxenstierna was widowed in 1631.
On 2 February 1639, she was appointed mistress of the robes to queen Christina. After the death of the queen's foster mother and aunt, Catherine of Sweden, Countess Palatine of Kleeburg in 1638, the council judiciously decided that the queen should have not one, but two foster mothers, as well as two mistress of the robes. The reason for splitting these two positions in four, was the wish that Christina should not be dependent upon one single individual and favorite. In 1639, the position of Mistress of the Robes was thereby shared between Beata Oxenstierna and Ebba Ryning (though the former was given a higher rank), and the position of foster mother was shared by Ebba Mauritzdotter Leijonhufvud and Christina Natt och Dag. Formally, however, also Leijonhufvud and Natt och Dag was given the title of Mistress of the Robes in name, though not in regard to their task. Leijonhufvud was related to Councillor Oxenstierna by marriage, which is believed to have played a part in why she was given her position: Beata Oxenstierna and Ebba Ryning was also connected to the Oxenstierna party.
Beata Oxenstierna is described thus: "A charitable lady, who did much good at court".