| Yossef Harmelin | |
| Native Name: | יוסף הרמלין |
| Native Name Lang: | he |
| Birth Date: | 1922 |
| Birth Place: | Vienna, Austria |
| Office1: | Director of the Shin Bet |
| Term Start1: | 1964 |
| Term End1: | 1974 |
| Predecessor1: | Amos Manor |
| Successor1: | Avraham Ahituv |
| Term Start2: | 1986 |
| Term End2: | 1988 |
| Predecessor2: | Avraham Shalom |
| Successor2: | Yaakov Peri |
| Office3: | Israeli Ambassador to Iran |
| Term End3: | 1979 |
| Office4: | Israeli Ambassador to South Africa |
| Allegiance: |  Israel |
| Branch: | Israel Defense Forces |
| Serviceyears: | 1940s–1949 |
| Battles: | 1948 Arab–Israeli War |
Yossef Harmelin (1922 – December 12, 1994) was an Israeli civil servant, serving as the director of the Shabak from 1964 to 1974 and again from 1986 to 1988 and as ambassador in Iran and South Africa.
Born in Vienna, Harmelin was active in Maccabi youth movement and the Hakoah Vienna Jewish sports club. He immigrated to Mandatoy Palestine in 1939 under the Youth Immigration program. He was first at Ben Shemen Youth Village and then founded kibbutz Neve Yam. Harmelin fought with the Israel Defense Forces in the 1948 Arab–Israeli War. He joined the shabak in 1949 and became deputy director of Shabak in 1960, rising to his first term as director four years later. In 1974, he left Shabak to pursue other interests, including his ambassadorship. He was the last Israeli ambassador to Iran, before diplomatic relations were severed following the Iranian Revolution.He returned to head the security agency again in 1986 following the Bus 300 affair. He retired in 1988.