Founded and led by Gustavo Riojas Santana, it was a center-left party which advocated nationalist policies.

The PSN was widely considered to be a "family party" since most of the party's top offices were occupied by relatives of Riojas Santana, allegedly for personal benefit.

In the Mexican general election of July 2, 2000, the party was a member of the Alliance for Mexico, nominating Cuauhtémoc Cárdenas as its presidential candidate.

In the 2003 midterm elections the PSN ran on its own and failed to obtain any seats in either chamber of the Mexican Congress.

Shortly thereafter, the Federal Electoral Institute fined Riojas Santana for misuse of the public funds it assigned to the PSN for campaign purposes.