| Competition: | Primera B de Chile |
| Season: | 1998 |
| Winners: | Cobresal |
| Promoted: | Cobresal O'Higgins Santiago Morning |
| Relegated: | Deportes Colchagua |
| Prevseason: | 1997–C |
| Nextseason: | 1999 |
The 1998 Primera B de Chile was the 48th completed season of the Primera B de Chile.
Cobresal was tournament’s champion[1] and was promoted to 1999 Primera División de Chile alongside O'Higgins and Santiago Morning, which achieved the promotion in the Promotion Playoffs.
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