1998–99 Primera División A season

Ascenso MX
Season1998–99
ChampionsApertura: Yucatán (1st Title)
Clausura: Unión de Curtidores (1st title)
PromotedUnión de Curtidores
RelegatedSan Francisco
Top goalscorerInvierno: Cristián Ariel Morales (19)
Verano: Ángel Lemus (16)

Primera División A (Méxican First A Division) is a Mexican football tournament. This season was composed of Invieno 1998 and Verano 1999. Unión de Curtidores, Verano 1999 champion, were able to gain promotion to Primera Division for the 1999-2000 season after winning the playoff to Yucatán, Invierno 1998 champion. However, the Puebla F.C. acquired the franchise belonging to Union de Curtidores to remain in the First Division.