Lazar Branković (Serbian Cyrillic: Лазар Бранковић) was a Serbian despot, prince of Rascia from 1456 to 1458. He was the third son of Đurađ Branković and his wife Eirene Kantakouzene. He was succeeded by his elder brother, despot Stefan III Branković.
Both Grgur and Stefan, his older brothers, were blinded by orders of Murad II in 1441. Lazar apparently became the heir to their father as the only son not to be handicapped. Đurađ died on 24 December 1456. Lazar succeeded him as planned.
His brief reign mostly included family quarrels with his mother and siblings. In 1457, Lazar gave an oath of subservience to Mehmed II, son and successor of Murad II, as an attempt to prevent an Ottoman invasion. His only other decision of consequence was to appoint Mihailo Anđelović, a member of the Angelos family, as his chief official. Mihailo would briefly serve as head of a regency council following the death of his lord.
Lazar died on 20 February 1458. George Sphrantzes recorded the date but not the cause.