Judith of Poland (Polish: Judyta Bolesławówna, Hungarian: Judit lengyel hercegnő, German: Judith von Polen; b. c. 1130/35 – died 8 July 1171/75), was a Polish princess member of the House of Piast and by marriage Margravine of Brandenburg.

She was the daughter of Bolesław III Wrymouth, Duke of Poland, by his second wife Salomea, daughter of Henry, Count of Berg. She was probably named after either her paternal grandmother, Judith of Bohemia or her older half-sister, Princess consort of Murom.

Judith was one of the youngest children of her parents; her date of birth remains unknown. According to Polish medieval chronicles, she was sent to Hungary as a bride of the son of King Béla II. According to the Annales Cracovienses Compilati, this event took place in 1136; since it can be assumed that the Polish princess was younger than her betrothed, and also are known the birth dates of the youngest children of Bolesław III (Agnes in 1137 and Casimir in 1138), Judith in consequence could have been born between 1130 and 1135.

The marriage never took place: by 1146, the engagement was broken with the consent of both parties and Judith returned to Poland. The reason for this may have been the wedding of Mieszko (Judith's brother) with the Hungarian princess Elisabeth (daughter of King Béla II), which sufficiently secured the Polish-Hungarian alliance.

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