1920–21 Primera Fuerza season

Due to the separation of the leagues, the champions were annulled by the amateur organizing body, which was the Asociación de Aficionados de México en la Liga de Football (English: The Mexico Amateur Association in the Football League).

The 5 participating clubs from Mexico City, and all the matches were played at Parque Asturias.

In replacement Deportivo Internacional and Club Morelos joined the league.

The 5 participating teams from Mexico City, and all the matches were played at Parque España.

Reforma AC, Club América, Luz y Fuerza and L'Amicale Française joined the Liga Nacional.