| Birth Name: | Clemens Henricus Jeltes |
| Birth Date: | 1924 3, df=y |
| Birth Place: | The Hague, Netherlands |
| Death Place: | Nederhorst den Berg, Netherlands |
| Occupation: | Sailor, measurer |
| Awards: | Ridder in de Orde van Oranje Nassau |
Clemens Henricus "Clé" Jeltes (11 March 19243 July 2010) was a Dutch sailor and measurer at seven Olympic games. He was heavily involved with the technical development of the Flying Dutchman and was the driving force to focus at boat measurement to the parameters that really matter. From 1968 until 1992, he was the International FD measurer at seven consecutive Olympic Games, making sure that the sailing took place in correct boats. He was appointed the Ridder in de Orde van Oranje Nassau in 2002 for, among other things, his services to sailing.