The 2009–10 Liga Nacional de Básquet season was the 26th season of the top professional basketball league in Argentina. The regular season started on 7 October 2009. Peñarol won their second title, defeating Atenas in the finals.
Promotions and relegations Torneo Nacional de Ascenso Champions from the previous season La Unión and runners-up Unión de Sunchales were promoted, occupying the berths left by Ben Hur and Monte Hermoso. Central Entrerriano, also from the second-tier tournament, traded places with Independiente de Neuquén, who had to sell their berth due to financial difficulties.Vuelve Central Entrerriano, pickandroll.net, 24 June 2009. Retrieved 22 May 2018.
Clubs Team City Arena Capacity Atenas Córdoba Carlos Cerutti 3,730 Bahía Blanca Estudiantes Bahía Blanca Osvaldo Casanova 3,950 Boca Juniors Buenos Aires Luis Conde 2,000 Central Entrerriano Gualeguaychú Estadio José María Bértora 2,000 Ciclista Olímpico La Banda Luis Conde 2,000 Gimnasia y Esgrima (Comodoro Rivadavia) Comodoro Rivadavia Socios Fundadores 2,276 Juventud Sionista Paraná Estadio Moisés Flesler 2,100 Lanús Lanús Antonio Rotili 4,000 Libertad Sunchales El Hogar de los Tigres 4,000 Obras Sanitarias Buenos Aires Estadio Obras 3,100 Peñarol Mar del Plata Islas Malvinas 8,000 Quilmes Mar del Plata Estadio Once Unidos 2,000 Quimsa Santiago del Estero Estadio Ciudad 5,200 Regatas Corrientes Corrientes José Jorge Contte 4,000 La Unión Formosa Cincuentenario 4,500 Unión de Sunchales Sunchales La Fortaleza del BichoColiseo del SurUnión será local en Rafaela, pickandroll.net, 25 July 2009. Retrieved 22 May 2018.
Regular season First stage The first stage took place between 7 October and 25 November 2009. Teams were divided into two zones. The top three teams from each zone plus the best fourth team overall and a wildcard competed in the Torneo Súper 8 that took place in December.
North Zone
South Zone
Torneo Súper 8 The sixth edition of Torneo Súper 8 took place on 17–20 December 2009 in the city of Mar del Plata. Peñarol won their second title, defeating Atenas in the Final.
Second stage The second stage started on 27 November 2010. All 16 teams were ranked together. Each team carried over half of the points obtained in the first stage.
Playoffs Championship playoffs The Playoffs started on 31 March 2011 and ended on 25 May 2011. Peñarol defeated Atenas in the Finals.
Relegation playoffs The relegation series began on 2 April. Central Entrerriano and Quilmes lost their respective series and were relegated to the Torneo Nacional de Ascenso.
Clubs in international competitions Team Competition Progress Atenas FIBA Americas League Group stage Obras Sanitarias Group stage Peñarol Champions Quimsa Final four Libertad Liga Sudamericana de Básquetbol Final four Juventud Sionista Quimsa Champions
Awards Yearly Awards Most Valuable Player: Leonardo Gutiérrez, Peñarol All-Tournament Team: F Leonardo Gutiérrez, Peñarol F Juan Locatelli, Atenas C Román González, Quimsa G Juan Pablo Figueroa, Atenas G David Jackson, Libertad
References LNB Media Guide 2016/2017, laliganacional.com.ar. Retrieved 16 May 2017.