1983–84 Yugoslav First Basketball League

The 1983–84 Yugoslav First Basketball League season was the 40th season of the Yugoslav First Basketball League, the highest professional basketball league in SFR Yugoslavia.

Playoff
Teams placed 1st to 6th at the end of the regular season automatically qualified for the playoffs quarterfinal round.

The remaining two spots for the playoffs quarterfinal round were determined through a four-team play-in. The 7th and 8th-placed teams had to play a single-game round against the Second League 2nd and 1st-placed teams, respectively, that managed to gain promotion for the next season's top league competition. Seventh-placed Partizan from the First League thus played 2nd-placed Sloga Kraljevo from the Second League. Similarly, 8th-placed Budućnost from the First League played 1st-placed Radnički Belgrade from the Second League. The winners of each respective game qualified for the playoffs quarterfinal.

SINGLE GAME PLAY-IN QUALIFYING (played in Hala Jezero, Kragujevac)

Budućnost-Radnički 66-83

Partizan-Sloga 99-93

QUARTERFINALS

Cibona-Radnički 101–88, 89–91, 101–89

Crvena zvezda-Partizan 93–79, 90–88

Zadar-Borac Čačak 91–83, 118–97

Šibenka-Bosna 88–94, 68–84

SEMIFINALS

Cibona-Bosna 99–89, 83–85, 77–75

Crvena zvezda-Zadar 112–90, 98–99, 112–84

FINALS

Cibona-Crvena zvezda 78–76, 79–87, 72–71

The winning roster of Cibona:
 * Mihovil Nakić
 * Aleksandar Petrović
 * Adnan Bečić
 * Damir Pavličević
 * Andro Knego
 * Sven Ušić
 * Rajko Gospodnetić
 * Zoran Čutura
 * Mladen Cetinja
 * Miro Jelavić
 * Marjan Nikšić
 * Franjo Arapović
 * Joško Vukičević
 * Ivo Nakić
 * Branko Vukićević

Coach: Mirko Novosel

Qualification in 1984–85 season European competitions
FIBA European Champions Cup
 * Cibona (champions)

FIBA Cup Winners' Cup
 * Bosna (Cup winners)

FIBA Korać Cup
 * Crvena Zvezda (2nd)
 * Zadar (3rd)
 * Šibenka (4th)
 * Borac Čačak (6th)