| Birth Date: | 26 February 1947 |
| Birth Place: | Amsterdam, the Netherlands |
| Death Date: | 14 October 2004 (aged 57) |
| Death Place: | Amsterdam, the Netherlands |
| Height: | 2.13m (06.99feet) |
| Weight: | 135kg (298lb) |
| Sport: | Judo |
| Show-Medals: | yes |
Peter Adelaar (26 February 1947 – 14 October 2004) was a Dutch judoka. Between 1973 and 1980 he won one gold and five bronze medals at European championships. He competed at the 1980 Summer Olympics in the heavyweight and open categories and finished in 10th and 15th place, respectively.