| Roles | Competed in Olympic Games | |
|---|---|---|
| Sex | Male | |
| Full name | Koos Marinus•de Haas | |
| Used name | Koos•de Haas | |
| Born | 10 September 1889 in Amsterdam, Noord-Holland |  NED |
| Died | 30 September 1966 (aged 77 years 20 days) in Den Haag (The Hague), Zuid-Holland | NED |
| Affiliations | De Amstel — Amsterdam, Noord-Holland | NED |
| NOC | Netherlands | NED |
| Games | Discipline (Sport) / Event | NOC / Team | Pos | Medal | As | |
|---|---|---|---|---|---|---|
| 1920 Summer Olympics | Rowing | NED |
Koos de Haas | |||
| Double Sculls, Men (Olympic) | Bastiaan Veth | 2 h2 r1/2 |
