| 1991 South American Championships in Athletics | |
| Host City: | Manaus, Brazil |
| Nations Participating: | 11 |
| Athletes Participating: | 257 |
| Events: | 41 |
| Dates: | 28–30 June |
| Stadium: | Vila Olímpica de Manaus |
| Previous: | Medellín 1989 |
| Next: | Lima 1993 |
The 36th South American Championships in Athletics were held in Manaus, Brazil, between 28 and 30 June 1991. It was the last edition to hold the Marathon event.
| 100 metres (wind: +0.7 m/s) | Robson da Silva | 10.18 | Arnaldo da Silva | 10.39 | Carlos Moreno | 10.44 | |
| 200 metres (wind: +0.5 m/s) | Robson da Silva | 20.79 | Marcelo Brivilati da Silva | 20.94 | Jesús Malavé | 21.18 | |
| 400 metres | Carlos Morales | 46.55 | Roberto Bortolotto | 46.90 | Henry Aguiar | 47.02 | |
| 800 metres | Flavio Godoy | 1:47.94 | Luiz José Gonçalves | 1:48.16 | Pablo Squella | 1:48.21 | |
| 1500 metres | Edgar de Oliveira | 3:42.41 | Luiz José Gonçalves | 3:42.48 | Carlos Naput | 3:50.09 | |
| 5000 metres | Valdenor dos Santos | 14:09.03 | Otoniel dos Santos | 14:13.35 | Eduardo Navas | 14:16.06 | |
| 10,000 metres | Valdenor dos Santos | 29:25.20 | Juan José Castillo | 29:37.40 | Roberto Punina | 30:00.40 | |
| Marathon | Joseildo Rocha | 2:33:22 | Luis Nempo | 2:39:57 | Doval da Silva | 2:41:38 | |
| 3000 metres steeplechase | Adauto Domingues | 8:36.21 CR | Wander Moura | 8:49.11 | Oscar Amaya | 8:52.08 | |
| 110 metres hurdles (wind: -1.1 m/s) | Joilto Bonfim | 14.11 | Elvis Cedeño | 14.23 | Eliexer Pulgar | 14.38 | |
| 400 metres hurdles | Eronilde de Araújo | 49.65 CR | Antonio Smith | 50.14 | Luis Bello | 50.73 | |
| 4 × 100 metres relay | Joilto Bonfim Arnaldo da Silva Robson da Silva Reginaldo Aguiar | 39.90 | Carlos Morales Carlos Moreno Héctor Fernández Roberto Marshall | 40.61 | Claudio Molocznik Guillermo Cacián José María Beduino Claudio Arcas | 41.22 | |
| 4 × 400 metres relay | Roberto Bortolotto Jorge Costa Geraldo Maranhão Jr. Ediélson Tenório | 3:05.60 CR | Antonio Smith Henry Aguiar José Moisés Zambrano Luis Bello | 3:08.39 | Claudio Arcas José María Beduino Guillermo Cacián Claudio Molocznik | 3:11.10 | |
| 20 kilometres road walk | Sérgio Galdino | 1:26:26 | Querubín Moreno | 1:28:56 | Orlando Díaz | 1:30:22 | |
| High jump | Gilmar Mayo | 2.20 CR | Fernando Moreno | 2.17 | Jorge Archanjo | 2.11 | |
| Pole vault | Cristián Aspillaga | 5.00 | Konstantín Zagustín | 5.00 | Thomas Riether | 4.80 | |
| Long jump | Paulo de Oliveira | 7.83 | Gelson Vaqueiro | 7.46 | Jimmy Ávila | 7.40 | |
| Triple jump | Anísio Silva | 16.15 | Sergio Saavedra | 15.98 | Ednilson de Miranda | 15.74 | |
| Shot put | Gert Weil | 18.37 | Adilson Oliveira | 18.08 | Yojer Medina | 16.35 | |
| Discus throw | João dos Santos | 58.08 CR | Marcelo Pugliese | 53.08 | Jair Teutonio | 51.62 | |
| Hammer throw | Adrián Marzo | 65.12 | Andrés Charadia | 62.88 | Pedro Rivail Atílio | 61.32 | |
| Javelin throw | Luis Lucumí | 74.42 | Rodrigo Zelaya | 73.88 | Gustavo Wielandt | 68.64 | |
| Decathlon | José de Assis | 7227 | Marco Antônio Brito | 6189 | Giovanny Gudino | 4617 |
| 100 metres (wind: -1.1 m/s) | Claudete Alves Pina | 11.84 | Berenice Ferreira | 11.93 | Alejandra Quiñones | 11.96 | |
| 200 metres (wind: +0.1 m/s) | Ximena Restrepo | 23.21 CR | Claudete Alves Pina | 23.37 | Eliane de Souza | 23.92 | |
| 400 metres | Maria Figueirêdo | 51.56 CR | Eliane de Souza | 53.76 | Ángela Mancilla | 54.11 | |
| 800 metres | Maria Figueirêdo | 2:00.45 CR | Luciana Mendes | 2:04.44 | Amparo Alba | 2:07.60 | |
| 1500 metres | Rita de Jesus | 4:19.18 CR | Célia dos Santos | 4:21.64 | Amparo Alba | 4:29.48 | |
| 3000 metres | Carmem de Oliveira | 9:17.50 CR | Rita de Jesus | 9:24.44 | Ruth Jaime | 9:39.04 | |
| 10,000 metres | Carmem de Oliveira | 33:27.85 CR | Solange de Souza | 34:00.90 | Sandra Ruales | 34:57.00 | |
| 100 metres hurdles (wind: -1.8 m/s) | Carmen Bezanilla | 13.73 | Arlene Phillips | 13.85 | Anabella von Kesselstatt | 14.20 | |
| 400 metres hurdles | Liliana Chalá | 57.16 CR | Maribelsy Peña | 57.23 | Arlene Phillips | 58.42 | |
| 4 × 100 metres relay | Rita Gomes Berenice Ferreira Cleide Amaral Eliane de Souza | 44.87 | Ángela Mancilla Elia Mera Alejandra Quiñones Ximena Restrepo | 45.00 | Daniela Lebreo Anabella von Kesselstatt Virginia Lebreo Denise Sharpe | 46.14 | |
| 4 × 400 metres relay | Maria Magnólia Figueiredo Jucilene Garcez Janice Vera Cruz Luciana Mendes | 3:32.59 CR | Ximena Restrepo María Quiñones Maribelcy Pena Ángela Quiñones | 3:36.56 |  Inés Justet Soledad Acerenza Laura Abel Claudia Acerenza | 3:40.19 NR | |
| 10,000 metres track walk | Gloria Moreno | 52:40.5 | Bertha Vera | 52:53.2 | Ivana Henn | 53:38.1 | |
| High jump | Orlane dos Santos | 1.89 CR | Mônica Lunkmoss | 1.81 | Leonor Carter | 1.75 | |
| Long jump | Rita Slompo | 5.94 | Luciana dos Santos | 5.78 | Ingrid Meilicke | 5.51 | |
| Shot put | María Isabel Urrutia | 16.34 CR | Elisângela Adriano | 16.04 | Alexandra Amaro | 14.95 | |
| Discus throw | María Isabel Urrutia | 51.70 CR | Fátima Germano | 49.74 | Rosana Piovesan | 47.80 | |
| Javelin throw | Marieta Riera | 57.40 CR | Sueli dos Santos | 56.64 | Mônica Rocha | 50.26 | |
| Heptathlon | Zorobabelia Córdoba | 5564 | Conceição Geremias | 5277 | Ana Lúcia Silva | 4837 |