Dejan Brđović started his professional career with OK Žiča and in 1985 played with Ribnica Kraljevo before playing with Crvena zvezda Belgrade from 1985-91, winning the Yugoslav Cup with them in 1991. From 1992-95 Brđović played in Greece, the first two seasons with Olimpiakos and the last with AC Orestias. The next six seasons, Brđović played with Auselda Rome in Italy, with Crvena zvezda Belgrade, winning the Serbuan Cup in 1997, with Volley Milano, Pallavolo Loreto, and Volley Lube (all in Italy) and AEK (in Greece), before finishing his career again with Crvena zvezda Belgrade from 2002-2003, winning the Serbian title in 2003, and Radnički Kragujevac from 2003-2006.
Internationally Brđović was capped with the Yugoslav, and later Serbian national teams, nearly 300 times between 1985-97. He won an Olympic bronze in 1996, an European Championships bronze in 1995, silver at the 1991 Mediterranean Games, and gold at the 1987 Universiade. After finishing his playing career, Brđović worked as a volleyball coach, with Radnički Kragujevac, Asystel Novara in Italy, Rabitə Bakı in Azerbaijan, and the Crvena zvezda Belgrade women’s team. He also worked as a general director of Ribnica Kraljevo.