At the 2002 FIFA World Cup, each national association was required to name a squad of 23 players, expanded from 22 in previous tournaments.
The players' ages, caps and clubs are as of 31 May 2002, the opening day of the tournament.
Head coach: Morten Olsen
Head coach: Roger Lemerre
Head coach: 
Bruno Metsu
Head coach: Víctor Púa
Head coach: 
Cesare Maldini
Head coach: Srečko Katanec
*Was expelled from the squad after the first game.Note: caps for Yugoslavia are not counted.
Head coach: Jomo Sono
Head coach: José Antonio Camacho
Head coach: Luiz Felipe Scolari
Head coach: Bora Milutinović
Head coach: Alexandre Guimarães
Head coach: Şenol Güneş
Head coach: Jerzy Engel
Head coach: António Oliveira
Head coach: 
Guus Hiddink
Head coach: Bruce Arena
Head coach: 
Winfried Schäfer
Head coach: Rudi Völler
Head coach: Mick McCarthy
Head coach: Nasser Al-Johar
Head coach: Marcelo Bielsa
Originally, the squad was named with Ariel Ortega given shirt number 23 and Roberto Bonano number 24, as the Argentine Football Association had decided to retire the number 10 shirt in honour of Diego Maradona. FIFA, however, insisted that all squads were assigned with numbers ranging only from 1–23, prompting Argentina to amend their squad list.
Head coach: 
Sven-Göran Eriksson
Head coach: Festus Onigbinde
Head coaches: Lars Lagerbäck and Tommy Söderberg
Head coach: Mirko JozićNote: caps for Yugoslavia are not counted.
Head coach: 
Hernán Darío Gómez
Head coach: Giovanni Trapattoni
Head coach: Javier Aguirre
Head coach: Robert Waseige
Head coach: Philippe Troussier
Head coach: Oleg RomantsevNote: caps include those for USSR, CIS, and Russia, while those for other countries, such as Ukraine, are not counted.
Head coach: Ammar Souayah
| Country | Players | Percent | Outside national squad | |
|---|---|---|---|---|
| Total | 736 | |||
| England | 103 | 13.99% | 81 | |
| Italy | 75 | 10.19% | 53 | |
| Germany | 59 | 8.02% | 39 | |
| Spain | 58 | 7.88% | 36 | |
| France | 56 | 7.61% | 51 | |
| Mexico | 25 | 3.40% | 6 | |
| Japan | 25 | 3.40% | 6 | |
| Belgium | 25 | 3.40% | 10 | |
| Saudi Arabia | 24 | 3.13% | 1 | |
| China | 21 | 2.85% | 1 | |
| Others | 266 | 36.14% |
The Saudi Arabian squad was the only one made up entirely of players from their country's domestic league and the only one with no players from European clubs. The Cameroonian squad were made up entirely of players employed by overseas clubs, while the Irish squad was made up entirely by players in the English league. Although the Netherlands and Greece failed to qualify for the finals, their domestic leagues were represented by 18 and 10 players respectively. Altogether, there were 43 national leagues who had players in the tournament.
| Nº | Country | Coaches |
|---|---|---|
| 3 | France | Roger Lemerre, Bruno Metsu (Senegal), Philippe Troussier (Japan) |
| Sweden | Sven-Göran Eriksson (England), Lars Lagerbäck, Tommy Söderberg | |
| 2 | Germany | Winfried Schäfer (Cameroon), Rudi Völler |
| Italy | Cesare Maldini (Paraguay), Giovanni Trapattoni | |
| 1 |  Argentina | Marcelo Bielsa |
 Belgium | Robert Waseige | |
 Brazil | Luiz Felipe Scolari | |
| Colombia | Hernán Darío Gómez (Ecuador) | |
 Costa Rica | Alexandre Guimarães | |
 Croatia | Mirko Jozić | |
 Denmark | Morten Olsen | |
| FR Yugoslavia | Bora Milutinović (China PR) | |
 Mexico | Javier Aguirre | |
| Netherlands | Guus Hiddink (South Korea) | |
 Nigeria | Festus Onigbinde | |
 Poland | Jerzy Engel | |
 Portugal | António Oliveira | |
| Republic of Ireland | Mick McCarthy | |
| Russia | Oleg Romantsev | |
 Saudi Arabia | Nasser Al-Johar | |
 Slovenia | Srečko Katanec | |
 South Africa | Jomo Sono | |
 Spain | José Antonio Camacho | |
 Tunisia | Ammar Souayah | |
 Turkey | Şenol Güneş | |
 United States | Bruce Arena | |
 Uruguay | Víctor Púa |