The 1991–92 Argentine Primera B Nacional was the sixth 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.
The Second Promotion Playoff or Torneo Reducido was played by the teams placed 2nd to 10th in the overall standings: Almirante Brown (2nd), who entered in the Semifinals, Colón (3rd), who entered in the Second Round, San Martín (T) (4th), Douglas Haig (5th), Nueva Chicago (6th), Instituto (7th), Atlético Tucumán (8th), Chaco For Ever (9th) and Talleres (RE) (10th), the champion of Primera B Metropolitana: Ituzaingó, and Arsenal and Gimnasia y Tiro, both winners of Zonales Noroeste y Sureste from Torneo del Interior entered in the First Round.
Note: San Martín de Tucumán won 2–1 on aggregate, promoting to Primera División Note: Clubs with indirect affiliation with AFA are relegated to their respective league of his province according to the Argentine football league system, while clubs directly affiliated face relegation to Primera B Metropolitana.
Clubs with direct affiliation are all from Greater Buenos Aires, with the exception of Newell's, Rosario Central, Central Córdoba and Argentino de Rosario, all from Rosario, and Unión and Colón from Santa Fe.