| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 1. I Papaioannou vs Kulaots |
| 0-1 | 35 |
1992 |
Wch U16 | A31 English, Symmetrical, Benoni Formation |
| 2. I Papaioannou vs Svidler |
| 0-1 | 37 |
1992 |
ChWmU16 Duisburg | D80 Grunfeld |
| 3. I Rogers vs I Papaioannou |
| ½-½ | 43 |
1995 |
op Agios Nikolaos GRE | E00 Queen's Pawn Game |
| 4. Kotronias vs I Papaioannou |
| 1-0 | 40 |
1996 |
Ch Greece | B12 Caro-Kann Defense |
| 5. Tringov vs I Papaioannou |
| ½-½ | 46 |
1997 |
Ikaros/Thessaloniki | B14 Caro-Kann, Panov-Botvinnik Attack |
| 6. I Papaioannou vs T Gelashvili |
| ½-½ | 44 |
1997 |
Ikaros/Thessaloniki | A62 Benoni, Fianchetto Variation |
| 7. I Nikolaidis vs I Papaioannou |
| ½-½ | 13 |
1998 |
48th Greek Championships | B40 Sicilian |
| 8. I Papaioannou vs H Banikas |
| ½-½ | 6 |
1998 |
48th Greek Championships | A00 Uncommon Opening |
| 9. I Papaioannou vs D Mastrovasilis |
| 1-0 | 77 |
1998 |
48th Greek Championships | D30 Queen's Gambit Declined |
| 10. I Papaioannou vs D Agnos |
| ½-½ | 31 |
1998 |
48th Greek Championships | B20 Sicilian |
| 11. I Papaioannou vs T Gelashvili |
| ½-½ | 33 |
1998 |
Korinthos op 2nd | A41 Queen's Pawn Game (with ...d6) |
| 12. K Markidis vs I Papaioannou |
| 0-1 | 36 |
1998 |
48th Greek Championships | B17 Caro-Kann, Steinitz Variation |
| 13. Skembris vs I Papaioannou |
 | 0-1 | 65 |
1998 |
48th Greek Championships | A70 Benoni, Classical with 7.Nf3 |
| 14. I Papaioannou vs T Gelashvili |
 | 1-0 | 38 |
1998 |
Ikaria op | A04 Reti Opening |
| 15. E Grivas vs I Papaioannou |
| 0-1 | 67 |
1998 |
48th Greek Championships | A30 English, Symmetrical |
| 16. I Papaioannou vs A Mastrovasilis |
 | ½-½ | 61 |
1998 |
48th Greek Championships | E00 Queen's Pawn Game |
| 17. I Papaioannou vs O Stefanopoulos |
| ½-½ | 15 |
1998 |
48th Greek Championships | A31 English, Symmetrical, Benoni Formation |
| 18. S Halkias vs I Papaioannou |
| ½-½ | 5 |
1998 |
48th Greek Championships | C48 Four Knights |
| 19. I Papaioannou vs T Gelashvili |
| 0-1 | 49 |
1999 |
GRE-chT 28th | E00 Queen's Pawn Game |
| 20. I Papaioannou vs T Gelashvili |
| 1-0 | 44 |
1999 |
Chania op 9th | E06 Catalan, Closed, 5.Nf3 |
| 21. I Papaioannou vs Beliavsky |
| ½-½ | 31 |
2000 |
34th Olympiad | E05 Catalan, Open, Classical line |
| 22. P Nikolic vs I Papaioannou |
| ½-½ | 35 |
2000 |
34th Olympiad | A30 English, Symmetrical |
| 23. I Papaioannou vs A David |
| ½-½ | 63 |
2000 |
34th Olympiad | B20 Sicilian |
| 24. Adams vs I Papaioannou |
 | 1-0 | 33 |
2000 |
34th Olympiad | B14 Caro-Kann, Panov-Botvinnik Attack |
| 25. J Egger vs I Papaioannou |
| 1-0 | 64 |
2000 |
34th Olympiad | B01 Scandinavian |