Bolesław Jerzy II Mazowiecki (Boleslaus George II of Masovia, also known as Yuriy II of Halicz and Bolesław Trojdenowicz) (1308-1340) was a ruler of the Piast dynasty.
Bolesław was born in 1308 to Trojden I of Masovia Duke of Czersk and Maria, daughter of Yuriy I , prince of Halicz. Since his father was still a ruler of his lands, in 1323 he became the Duke of Halicz. In 1331 he married the daughter of Giedymin, ruler of Lithuania, sister of Aldona Ana wife of Casimir III of Poland. In a treaty of 1338 Bolesław Jerzy offered Casimir III of Poland succession to the throne of Halicz. He was poisoned in 1340 and died heirless. After his death his domain was inherited by Poland.
