Borislav Kostić (aka Boris or Bora Kostic, Kostitsch) (February 24, 1887 – November 3, 1963) was a Serbian professional chess grandmaster from Vršac(Hungarian: Versecz; German: Werschetz), then in the Austro-Hungarian Empire (now Serbia).
Kostic played matches against Frank Marshall, Jackson Showalter, and Paul Leonhardt, and won them all. At Havana in 1919 however, this impressive winning streak came to an abrupt end with a 5–0 loss to Capablanca. Capablanca wrote that his own career peaked with this match. Kostic also played tournaments while in the United States, including New York 1916, Chicago 1918 and New York 1918, where he finished second behind Capablanca.
During World War II, Kostić (Orthodox Christian) was imprisoned in a concentration camp by a Nazi SS commander Schiller because he declined to participate in tournaments called "Free Europa" and to glorify the Nazi regime. Afterwards, he played chess only in a more minor capacity. His final appearance was at the Zürich veterans tournament of 1962, which he won. Kostic was awarded the Grandmaster title by FIDE in 1950, on its inaugural list. He died in Belgrade in 1963, aged 76.