| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 1. J O Fries Nielsen vs W Honigl |
| 1-0 | 42 |
1975 |
Hallsberg - int'l jr | C01 French, Exchange |
| 2. J O Fries Nielsen vs C Bjork |
| 1-0 | 35 |
1975 |
Hallsberg - int'l jr | B08 Pirc, Classical |
| 3. D Donchev vs J O Fries Nielsen |
| 1-0 | 42 |
1975 |
Hallsberg - int'l jr | C50 Giuoco Piano |
| 4. J O Fries Nielsen vs P Iten |
| 1-0 | 32 |
1975 |
Hallsberg - int'l jr | A46 Queen's Pawn Game |
| 5. C Doucet vs J O Fries Nielsen |
| 1-0 | 48 |
1975 |
Hallsberg - int'l jr | B74 Sicilian, Dragon, Classical |
| 6. J O Fries Nielsen vs C Bergstrom |
| 0-1 | 32 |
1975 |
Hallsberg - int'l jr | A00 Uncommon Opening |
| 7. J O Fries Nielsen vs L Madebrink |
 | 1-0 | 32 |
1975 |
Hallsberg - int'l jr | B56 Sicilian |
| 8. J O Fries Nielsen vs Petursson |
| 0-1 | 27 |
1975 |
Hallsberg - int'l jr | B52 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 9. J O Fries Nielsen vs Yusupov |
| 0-1 | 40 |
1977 |
Wch U20 | C55 Two Knights Defense |
| 10. Kasparov vs J O Fries Nielsen |
 | 1-0 | 53 |
1977 |
Cagnes sur mer | C69 Ruy Lopez, Exchange, Gligoric Variation, 6.d4 |
| 11. Larsen vs J O Fries Nielsen |
| 1-0 | 39 |
1978 |
Esbjerg | A10 English |
| 12. L Schneider vs J O Fries Nielsen |
| 1-0 | 28 |
1978 |
Esbjerg | B84 Sicilian, Scheveningen |
| 13. Hoi vs J O Fries Nielsen |
| ½-½ | 26 |
1978 |
Esbjerg | D25 Queen's Gambit Accepted |
| 14. J Rodgaard vs J O Fries Nielsen |
| ½-½ | 20 |
1978 |
Esbjerg | A15 English |
| 15. Yusupov vs J O Fries Nielsen |
| ½-½ | 20 |
1978 |
Wch U20 | A16 English |
| 16. J O Fries Nielsen vs A J Mestel |
| 1-0 | 39 |
1978 |
Esbjerg | A07 King's Indian Attack |
| 17. G Sigurjonsson vs J O Fries Nielsen |
| 1-0 | 34 |
1978 |
Esbjerg | B09 Pirc, Austrian Attack |
| 18. B Brinck-Claussen vs J O Fries Nielsen |
| 1-0 | 65 |
1978 |
Esbjerg | E47 Nimzo-Indian, 4.e3 O-O 5.Bd3 |
| 19. J O Fries Nielsen vs U Rath |
| 0-1 | 33 |
1978 |
Esbjerg | A15 English |
| 20. J O Fries Nielsen vs J Kristiansen |
| 1-0 | 57 |
1978 |
Esbjerg | A48 King's Indian |
| 21. J O Fries Nielsen vs J Sloth |
| ½-½ | 23 |
1978 |
Esbjerg | E62 King's Indian, Fianchetto |
| 22. Reshevsky vs J O Fries Nielsen |
| ½-½ | 42 |
1979 |
Esjberg | D97 Grunfeld, Russian |
| 23. E Mortensen vs J O Fries Nielsen |
| 1-0 | 29 |
1980 |
Copenhagen | A89 Dutch, Leningrad, Main Variation with Nc6 |
| 24. Yusupov vs J O Fries Nielsen |
| 1-0 | 57 |
1980 |
Esbjerg | E06 Catalan, Closed, 5.Nf3 |
| 25. E Ditt vs J O Fries Nielsen |
| ½-½ | 54 |
1980 |
Germany | A10 English |