The 1988–89 Argentine Primera B Nacional was the 3rd. season of second division professional of football in Argentina. A total of 22 teams competed; the champion and runner-up were promoted to Argentine Primera División. Chaco For Ever (champion) and Unión (SF) (winner of "Torneo Dodecagonal" after beating arch-rival Colón in a two-legged series) promoted to Primera División. On the other hand, Chacarita Juniors, Temperley, and Estación Quequén (Necochea) were relegated to Primera B.