| Koos de Jong | |
| Fullname: | Jacobus Hermanus Hendrik Jan de Jong |
| Nationality: | Dutch |
| Birth Date: | 7 April 1912 |
| Birth Place: | Rotterdam, the Netherlands[1] |
| Death Place: | Capelle aan den IJssel, the Netherlands |
| Height: | 195 cm[2] |
| Weight: | 100 kg |
| Classes: | Firefly, Finn |
| Show-Medals: | yes |
| Updated: | 2014-01-04 |
Jacobus Hermanus Hendrik Jan "Koos" de Jong (7 April 1912 – 20 August 1993) was a sailor from the Netherlands. He competed in the Firefly event at the 1948 Olympics and in the Finn event at the 1952 Games and won a bronze medal in 1948, placing fourth in 1952.[1] De Jong won several medals at European championships, including the gold in 1959.[2] [3]