Isailović came through the youth ranks of Red Star Belgrade, before making his senior debut with Rad.
He moved to Sevojno in late summer of 2005, staying at the club for a year and a half.
He subsequently moved abroad again and joined Polish club Zagłębie Lubin in January 2010.
On 14 December 2008, Isailović made his international debut for Serbia in a 0–1 friendly loss to Poland.
In June 2010, he was selected in Serbia's squad for the 2010 FIFA World Cup,[1] but didn't make any appearances.