| Competition: | Segunda División de México |
| Season: | 1990–91 |
| Winners: | Atlante (2nd Title) |
| Matches: | 423 |
| Total Goals: | 1027 |
| League Topscorer: | Jaime Ríos(23 goals) |
| Promoted: | Cachorros Zamora Guerreros Acapulco Zitlaltepec |
| Relegated: | Guerreros Acapulco Leones Saltillo Zitlaltepec Cachorros Zamora |
| Prevseason: | 1989–90 |
| Nextseason: | 1991–92 |
The 1990–91 Segunda División was the 42nd season of the Mexican Segunda División. The season started on 3 August 1990 and concluded on 17 July 1991. It was won by Atlante.[1]
| Club | City | Stadium | |
|---|---|---|---|
| Atlante | Mexico City | Estadio Azulgrana | |
| Atlético Potosino | San Luis Potosí | Estadio Plan de San Luis | |
| Bachilleres | Guadalajara | Estadio Tecnológico UdeG | |
| Cachorros Zamora | Zamora | Unidad Deportiva El Chamizal | |
| Chetumal | Chetumal | Estadio José López Portillo | |
| Ecatepec | Ecatepec de Morelos | Estadio Morelos | |
| Guerreros Acapulco | Acapulco | Unidad Deportiva Acapulco | |
| Inter de Tijuana | Tijuana | Estadio Cerro Colorado | |
| Jalisco | Guadalajara | Estadio Jalisco Club San Rafael | |
| La Piedad | La Piedad | Estadio Juan N. López | |
| Leones Saltillo | Saltillo | Estadio Olímpico Francisco I. Madero | |
| Pachuca | Pachuca | Estadio Revolución Mexicana | |
| Pioneros Cancún | Cancún | Estadio Cancún 86 | |
| Real Celaya | Celaya | Estadio Miguel Alemán Valdés | |
| Tecomán | Tecomán | Estadio IAETAC | |
| Tepic | Tepic | Estadio Nicolás Álvarez Ortega | |
| UAQ | Querétaro City | Estadio Corregidora | |
| Yucatán | Mérida | Estadio Carlos Iturralde | |
| Zacatepec | Zacatepec | Estadio Agustín "Coruco" Díaz | |
| Zitlaltepec | San Juan Zitlaltepec | Estadio Los Brujos |