| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 1. S Semkov vs Van der Wiel |
| 0-1 | 35 | 1976 | Wch U16 | A33 English, Symmetrical |
| 2. S Semkov vs Pinter |
 | 1-0 | 41 | 1977 | Varna | C56 Two Knights |
| 3. S Semkov vs Krum Georgiev |
| 0-1 | 21 | 1977 | Varna | B96 Sicilian, Najdorf |
| 4. I Radulov vs S Semkov |
| 1-0 | 29 | 1977 | Bulgaria | B45 Sicilian, Taimanov |
| 5. Savon vs S Semkov |
| 1-0 | 56 | 1982 | Varna 21st | D32 Queen's Gambit Declined, Tarrasch |
| 6. Vaisser vs S Semkov |
| 1-0 | 44 | 1982 | Chigorin Memorial | E39 Nimzo-Indian, Classical, Pirc Variation |
| 7. S Semkov vs Romanishin |
| 1-0 | 53 | 1982 | Chigorin Memorial | E60 King's Indian Defense |
| 8. S Semkov vs L Hazai |
| 0-1 | 41 | 1982 | Chigorin Memorial | E60 King's Indian Defense |
| 9. P Nikolic vs S Semkov |
| 1-0 | 38 | 1982 | Chigorin Memorial | A04 Reti Opening |
| 10. S Semkov vs Dvoirys |
| 0-1 | 57 | 1982 | Chigorin Memorial | D76 Neo-Grunfeld, 6.cd Nxd5, 7.O-O Nb6 |
| 11. Psakhis vs S Semkov |
| 1-0 | 112 | 1982 | Chigorin Memorial | D42 Queen's Gambit Declined, Semi-Tarrasch, 7.Bd3 |
| 12. Averkin vs S Semkov |
| ½-½ | 43 | 1982 | Chigorin Memorial | D35 Queen's Gambit Declined |
| 13. S Semkov vs Speelman |
| ½-½ | 54 | 1982 | Chigorin Memorial | A54 Old Indian, Ukrainian Variation, 4.Nf3 |
| 14. S Semkov vs Geller |
| ½-½ | 42 | 1982 | Chigorin Memorial | E47 Nimzo-Indian, 4.e3 O-O 5.Bd3 |
| 15. Chandler vs S Semkov |
| ½-½ | 42 | 1982 | Chigorin Memorial | B76 Sicilian, Dragon, Yugoslav Attack |
| 16. S Semkov vs A N Panchenko |
| 0-1 | 41 | 1982 | Chigorin Memorial | D51 Queen's Gambit Declined |
| 17. S Semkov vs Ftacnik |
| ½-½ | 64 | 1982 | Chigorin Memorial | D78 Neo-Grunfeld, 6.O-O c6 |
| 18. Pigusov vs S Semkov |
| 1-0 | 61 | 1982 | Chigorin Memorial | A04 Reti Opening |
| 19. Razuvaev vs S Semkov |
| 1-0 | 41 | 1982 | Chigorin Memorial | A62 Benoni, Fianchetto Variation |
| 20. S Semkov vs Tal |
| 0-1 | 39 | 1982 | Chigorin Memorial | B06 Robatsch |
| 21. G Andruet vs S Semkov |
| 0-1 | 25 | 1985 | BUL-FRA | D21 Queen's Gambit Accepted |
| 22. Tringov vs S Semkov |
| 1-0 | 58 | 1985 | Varna 24th | A07 King's Indian Attack |
| 23. S Semkov vs V Inkiov |
| 0-1 | 26 | 1985 | BUL-ch | E43 Nimzo-Indian, Fischer Variation |
| 24. S Semkov vs G Andruet |
| 0-1 | 34 | 1985 | BUL-FRA | E54 Nimzo-Indian, 4.e3, Gligoric System |
| 25. Kholmov vs S Semkov |
| 1-0 | 52 | 1987 | BUL | B47 Sicilian, Taimanov (Bastrikov) Variation |
Kibitzing
