1998 NBL season

The 1998 NBL season was the 20th season of competition since its establishment in 1979. A total of 11 teams contest the league. This season marked the NBL's final winter season. The Illawarra Hawks were renamed the Wollongong Hawks.

Regular season
The 1998 regular season took place over 19 rounds between 30 January 1998 and 9 June 1998.

Round 1
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 2
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 3
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 4
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 5
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 6
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 7
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 8
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 9
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 10
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 11
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 12
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 13
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 14
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 15
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 16
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 17
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 18
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Round 19
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Ladder
The NBL tie-breaker system as outlined in the NBL Rules and Regulations states that in the case of an identical win–loss record, the results in games played between the teams will determine order of seeding.

''1Brisbane Bullets won Head-to-Head (2-1). ''

''2Wollongong Hawks won Head-to-Head (2-1). ''

''3North Melbourne Giants won Head-to-Head (2-1). ''

Elimination Finals
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Semi-finals
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

Grand Final
!width=90| Date !width=180| Home !width=60| Score !width=180| Away !width=260| Venue !width=70| Crowd !width=70| Boxscore
 * - bgcolor="#CCCCFF" font size=1

NBL awards

 * Most Valuable Player: Andrew Gaze, Melbourne Tigers
 * Most Valuable Player Grand Final: Kevin Brooks, Adelaide 36ers
 * Best Defensive Player: Mike Kelly, South East Melbourne Magic
 * Most Improved Player: Ben Melmeth, Newcastle Falcons
 * Rookie of the Year: David Smith, North Melbourne Giants
 * Coach of the Year: Brian Goorjian, South East Melbourne Magic