Islah or Al-Islah (ألإصلاح ,إصلاح) is an arabic word usually translated as "reform", in the sense of "to improve, to better, or to put something into a better position." It is used in religion and politics (including as a name for political parties), and is also used as a personal and place name.
The word is an infinitive form derived from the roots sad-lam-ha (صلح), and according to author Josef W. Meri occurs in forty verses of the Qur'an where it means "to restore oneself or to reconcile people with one another, to make peace."  It is used most commonly today in Arabic with respect to the idea of reform, although this usage was not widespread until the modern reform movements of the 19th and 20th centuries, according to author Juan Eduardo Campo .
Islah may refer to:
- Islah, Qalqilya, Palestinian village in the West Bank
- Al-Islah Mosque, Hamtramck, Michigan, USA
- Al-Islah (Khaksar Tehrik weekly) (c. 1940), Indian newspaper
- Islah Jad (born 1951), Palestinian academic & activist
- Al-Islah, a.k.a. Yemeni Congregation for Reform, Yemeni opposition party
- Al Islah, Islamist group based in the United Arab Emirates that is affiliated with the Muslim Brotherhood
- El Islah, Mauritanian political party
- National Reform Trend, Iraqi political party
- Jamaah Islah Malaysia, Malaysian NGO
- Movement for National Reform, Algerian political party
- Reform Party of Syria, United States based lobbying organization
- Islah Party, an Egyptian Salafi political party
- The ISLAH Reparations Project, a USA based non- profit