| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 1. K Langeweg vs Bobotsov |
| ½-½ | 48 |
1961 |
Zevenaar | E70 King's Indian |
| 2. K Langeweg vs M Czerniak |
| 0-1 | 27 |
1963 |
IBM | E92 King's Indian |
| 3. K Langeweg vs Szabo |
| 0-1 | 39 |
1966 |
Beverwijk | E91 King's Indian |
| 4. K Langeweg vs F Kuijpers |
| ½-½ | 30 |
1967 |
NED-ch | E84 King's Indian, Samisch, Panno Main line |
| 5. K Langeweg vs M J Freeman |
| 0-1 | 30 |
1968 |
Olympiade | E69 King's Indian, Fianchetto, Classical Main line |
| 6. K Langeweg vs Bronstein |
| ½-½ | 19 |
1968 |
Amsterdam IBM | E62 King's Indian, Fianchetto |
| 7. K Langeweg vs J H Donner |
 | 0-1 | 32 |
1969 |
Wijk aan Zee I | E75 King's Indian, Averbakh, Main line |
| 8. K Langeweg vs J H Donner |
| ½-½ | 40 |
1970 |
Wijk aan Zee I | E77 King's Indian |
| 9. K Langeweg vs Najdorf |
| 1-0 | 74 |
1971 |
Wijk aan Zee | E75 King's Indian, Averbakh, Main line |
| 10. K Langeweg vs Nezhmetdinov |
| 0-1 | 24 |
1972 |
Chigorin Memorial | E94 King's Indian, Orthodox |
| 11. K Langeweg vs Savon |
| ½-½ | 14 |
1972 |
Hoogovens | E97 King's Indian |
| 12. K Langeweg vs A Planinc |
| 0-1 | 33 |
1973 |
IBM | E98 King's Indian, Orthodox, Taimanov, 9.Ne1 |
| 13. K Langeweg vs Ghitescu |
| 0-1 | 35 |
1974 |
Wijk aan Zee I | E82 King's Indian, Samisch, double Fianchetto Variation |
| 14. K Langeweg vs Geller |
| ½-½ | 37 |
1974 |
Amsterdam IBM | E97 King's Indian |
| 15. K Langeweg vs G Ligterink |
| 0-1 | 32 |
1976 |
Amsterdam IBM I | E97 King's Indian |
| 16. K Langeweg vs Timman |
| ½-½ | 34 |
1977 |
1, Leeuwarden NED ch | E94 King's Indian, Orthodox |
| 17. K Langeweg vs Van der Wiel |
| ½-½ | 25 |
1979 |
Leeuwarden NED ch | E73 King's Indian |
| 18. K Langeweg vs Van der Wiel |
| ½-½ | 24 |
1979 |
Amsterdam IBM II | E97 King's Indian |
| 19. K Langeweg vs Gheorghiu |
| ½-½ | 14 |
1981 |
Hoogovens | E91 King's Indian |
| 20. K Langeweg vs Van der Sterren |
| ½-½ | 28 |
1981 |
NED-ch | E92 King's Indian |
