| Youssef Borahil al-Mismari Arabic: يوسف بورحيل المسماري | |
| Birth Date: | 1886 |
| Birth Place: | Marj, Ottoman Libya |
| Nationality: | Libyan |
| Blank1: | Religion |
| Data1: | Sunni Islam |
| Allegiance: | Senussi Order |
| Branch: | Senussid Military Adwar |
| Battles: | |
| Known For: | Leading Arab native resistance to Italian colonization of Libya |
| Office3: | Leader of Senussi Tribal Military |
| Term3: | 16 September – 19 December 1931 |
| Predecessor3: | Omar al-Mukhtar |
Yousaf Borahil al-Mismari (Arabic: يوسف بورحيل المسماري) (ca. 1886 — 19 December 1931) was a Libyan revolutionary who fought against the Italian colonization of Libya. He also served as the deputy leader of the Libyan Jihad after the death of Omar Al-Mokhtar. He was killed in action after a confrontation with Italian security forces in Libya at the age of 45.