1978 World Amateur Championships - IFBB
| Overall Winner Tom Platz | |
HeavyWeight | |
| 1 | Mike Mentzer (United States) |
| 2 | Jusup Wilkosz (Germany) |
| 3 | Reid Schindle (Canada) |
| 4 | Chen Wint (Jamaica) |
| 5 | Steve Alters (Jamaica) |
| 6 | Ulf Bengtsson (Sweden) |
| 7 | Karl Kainrath (Austria) |
| 8 | Marc Devooght (Belgium) |
| 9 | Ken Bradshaw (Trinidad) |
| 10 | Christer Eriksson (Sweden) |
| 11 | Juhani Nyholm (Finland) |
| 12 | Mohamed Mawla (Lebanon) |
| 13 | Johannis Kostoglakis (Greece) |
| 14 | Jussi Kantola (Finland) |
MiddleWeight | |
| 1 | Tom Platz (United States) |
| 2 | Peter Stach (Czechoslovakia) |
| 3 | Darcy Beccles (Barbados) |
| 4 | Roy Chavez (United Kingdom) |
| 5 | Walter Bubenicek (Austria) |
| 5 | Andreas Cahling (Sweden) |
| 5 | Mike Watson (Canada) |
| 8 | Johnny Fuller (United Kingdom) |
| 8 | Jacques Neuville (France) |
| 10 | Filippo Alfani (Italy) |
| 10 | Erwin Note (Belgium) |
| 12 | Loftus Roach (Barbados) |
| 13 | Santos Ramos (Mexico) |
| 14 | Mederic Annette (France) |
| 15 | Karl Bloemer (Germany) |
| 16 | Frederick Smith (Jamaica) |
| 17 | Emilio DeRocha (Brazil) |
| 18 | Frederick Bittar (Brazil) |
| 19 | Erik Dokter (Netherlands) |
| 19 | Jorma Varhevaara (Norway) |
| 21 | Alfred Rieben (Switzerland) |
| 22 | Joseph Perez (New Zealand) |
| 23 | Gustavo Cuba (Venezuela) |
| 24 | Osamu Usui 臼井オサム (Japan) |
| 25 | Rolando Pintoy (Philippines) |
| 26 | Henri Hoeppner (Luxembourg) |
| 26 | Omar N'Gomb (Senegal) |
| 28 | Hussein El Tardi (Libya) |
| 28 | Arthur Elden (Bahamas) |
| 30 | Gustv Giovagnoli (Luxembourg) |
| 31 | Nouri Deliah (Libya) |
| 32 | Shalom Fillo (Israel) |
LightWeight | |
| 1 | Carlos Rodriguez (United States) |
| 2 | Renato Bertagna (Italy) |
| 3 | Robert Dantlinger (Czechoslovakia) |
| 4 | Bernard Sealy (Barbados) |
| 5 | Jorma Raty (Finland) |
| 6 | Moh Teck Hin (Singapore) |
| 7 | Rogelio Montenegro (Argentina) |
| 8 | Jean LeBlanc (Canada) |
| 9 | Adolf Ziegner (Austria) |
| 10 | Reinhard Heyd (Germany) |
| 11 | Ugo Romano (Italy) |
| 12 | Jose Rabanal (France) |
| 13 | Ludo Bouduin (Belgium) |
| 14 | Rudie Liesdek (Netherlands) |
| 15 | Akira Taniguchi 谷口明 (Japan) |
| 16 | Benedito Goncalves (Brazil) |
| 17 | Asencion Gonzales (Mexico) |
| 18 | Romeo Speccia (Switzerland) |
| 19 | Antonio Aprea (United Kingdom) |
| 20 | Yukitoshi Ono (Japan) |
| 21 | Ledgardo Lacson (Philippines) |
| 22 | Victor Mazuera (Columbia) |
| 23 | Roman Guzman (Columbia) |
| 24 | Tony Ashmore (Ireland) |
| 24 | Rene Faivre (Switzerland) |
| 24 | Edgar Rodriguez (Columbia) |
| 27 | Mufta Ibrahim (Libya) |
| 28 | Pilander Aragón (El Salvador) |