Beatrice of Bar (also Beatrix; c. 1020 – 18 April 1076) was the marchioness of Tuscany by marriage to Boniface III of Tuscany, and Regent of Tuscany from 1052 until her death, during the minority of and in co-regency with, her daughter Matilda. She was the daughter of Frederick II, Duke of Upper Lorraine, count of Bar, and Matilda of Swabia. She was married first to Boniface III of Tuscany and later to Godfrey of Lotharingia.