Laos competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's sixth appearance at the Olympics, having attended every edition of the Olympiad since 1980 except the 1984 Summer Olympics in Los Angeles, because of the Soviet boycott.
Mauritius competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's sixth consecutive appearance at the Olympics.
Fiji competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004.
El Salvador competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's eighth appearance at the Olympics.
The Gambia competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004.
Guatemala competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's eleventh appearance at the Summer Olympics, excluding three occasions after its national debut at the 1952 Summer Olympics in Helsinki.
Dominica competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. The country's participation at Athens marked its third appearance in the Summer Olympics since its debut in the 1996 Summer Olympics. Two track and field athletes, Chris Lloyd and Marie-Lyne Joseph were selected to represent the nation, the latter by a wildcard place as the nation had no other athletes that met either the "A" or "B" qualifying standards apart from Lloyd. Lloyd was selected as flag bearer for the opening ceremony.
Barbados competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This nation marked its ninth appearance at the Olympics, except the 1980 Summer Olympics in Moscow because of the United States boycott.
Ivory Coast competed at the 2004 Summer Olympics in Athens, Greece from 13 to 29 August 2004.
Nicaragua competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004.
Bermuda competed at the 2004 Summer Olympics in Athens, Greece from 13 to 29 August 2004. This was the nation's fifteenth appearance at the Olympics, except the 1980 Summer Olympics in Moscow.
Lesotho competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. It was the last time the nation competed under a former flag.
Grenada competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's sixth consecutive appearance at the Olympics.
Botswana competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004.
Yemen competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004.
Honduras competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004.
Panama competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's fourteenth appearance at the Olympics since its debut in 1920. Panama did not compete on four occasions, including the 1980 Summer Olympics in Moscow, because of its partial support of the United States boycott.
Suriname competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004.
Eritrea competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. The nation won its first Olympic medal ever at these Games, in its second appearance.
Nepal competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004.
