Sophia Jagiellon of Poland (Polish: Zofia Jagiellonka; 13 July 1522 – 28 May 1575), a member of the Jagiellonian dynasty, was a Polish princess and Duchess of Brunswick-Wolfenbüttel from 1556 to 1568 by her marriage with Duke Henry V.[1] Sophia was born in Kraków, a daughter of King Sigismund I of Poland (1467–1548) and his second wife, the Italian princess Bona Sforza (1494–1557).

When in 1548 her mother Bona Sforza entered into conflict with her son King Sigismund II Augustus over the marriage with his mistress Barbara Radziwiłł, Sophia and her sisters were removed from the Kraków court to live in Masovia.

The couple had eight children, though only one surviving son, Prince Julius, whose elder brothers were killed in the 1553 Battle of Sievershausen.

His father considered him an incapable ruler and wished for another heir to the throne; however, the second marriage with Sophia proved childless.

Shortly after, she fell into dispute with her stepson Duke Julius of Brunswick-Wolfenbüttel; the conflict, which concerned the scope of princely rule in the Schöningen estates, ended on 17 January 1572 when both signed an agreement.