| Halfdan Ditlev-Simonsen Jr. | |
| Nationality: | Norwegian |
| Sport: | Sailing |
| Birth Date: | 8 February 1924 |
| Birth Place: | Oslo, Norway |
| Death Place: | Oslo, Norway |
Halfdan Ditlev-Simonsen Jr. (8 February 1924 - 19 December 1989) was a Norwegian sailor. He competed in the 5.5 Metre event at the 1956 Summer Olympics.[1]