Ilija Plamenac (Илија Пламенац); 1821 - 23 February 1916) was a Montenegrin duke and military commander during the Montenegrin–Ottoman War (1876–1878). His Montenegrin ancestors came from the Crmnica tribe of Boljevići. Plamenac commanded the Montenegrin army in battles of Krnjice (1862), Fundina (1876), and then on Maljat (1876), Martinići (1877) and in the liberation of Bar and Ulcinj.
He is best remembered for the decisive Battle of Fundina. Together with Marko Miljanov Popović, Ilija Plamenac led a force of 5,000 men and defeated a Turkish army of 40,000 men under Mahmud Pasha. The Montenegrins inflicted at least 10,000 casualties for the loss of 600 men.
Plamenac was Montenego's Defence Minister from 1879 to 1905. He received the Russian Order of St. George 4th class, on 12 April 1877.
He was related to Jovan Plamenac, leader of the True People's Party.