| Joachim Gruppelaar | |
| Fullname: | Joachim Joseph Gruppelaar |
| Birth Date: | 24 October 1911 |
| Birth Place: | Amersfoort, the Netherlands |
| Death Date: | 12 July 1971 (aged 59) |
| Death Place: | Renkum, the Netherlands |
| Sport: | Horse riding |
| Show-Medals: | yes |
Joachim Joseph Gruppelaar (24 October 1911 – 12 July 1971) was a Dutch equestrian. He competed at the 1948 Summer Olympics in jumping and finished in 20th place. Gruppelaar held a military rank of major in 1948.