2011–12 Primera B Nacional
| Season | 2011–12 | 
|---|---|
| Champions | River Plate (1st divisional title)  | 
| Promoted | River Plate Quilmes  | 
| Relegated | Guillermo Brown Chacarita Juniors Desamparados Atlanta  | 
| Matches played | 380 | 
| Goals scored | 835 (2.2 per match) | 
| Top goalscorer | Gonzalo Castillejos (26 goals) | 
| Biggest home win | River Plate 7–1 Atlanta (5 October 2011) Quilmes 7–1 Independiente Rivadavia (24 February 2012)  | 
| Biggest away win | Gimnasia y Esgrima (J) 1–4 River Plate (5 November 2011) Guillermo Brown 1–4 River Plate (19 November 2011)  | 
| Longest winning run | 7 - Rosario Central (9 April – 19 May)  | 
| Longest unbeaten run | 19 - Instituto (10 September – 3 March)  | 
| Longest losing run | 12 - Gimnasia y Esgrima (J) (19 October – 11 February)  | 
← 2010–11  2012–13 →   | |
The 2011–12 Argentine Primera B Nacional was the 26th season of second division professional of football in Argentina. A total of 20 teams competed; the champion and runner-up were promoted to Argentine Primera División.