Ajami (Arabic: عجمي, romanized: ʿajamī) or Ajamiyya (عجمية, ʿajamiyyah), is a variety of Arabic-derived scripts used for writing African languages such as Songhai, Mandé, Fula, Hausa and Swahili, although multiple other languages are also written using the script, including Mooré, Wolof, Kanuri, and Yoruba. They are adaptations of the Arabic script to write sounds not found in Standard Arabic. Rather than adding new letters, modifications usually consist of additional dots or lines added to pre-existing letters.

The word Ajami comes from an Arabic word meaning foreign or stranger, referring to non-Arabic speakers, hence the term Ajami was used for non-Arabic languages written in Arabic script.

African languages were first written in Ajami scripts between the 10th and the 12th centuries. It likely was originally created with the intent of promoting Islam in West Africa. The first languages written in the script were likely old Taseelhit or medieval Amazigh, Kanuri, or Songhay.

The oldest surviving usage of Ajami comes from 13th century tomb inscriptions in modern-day Niger, where Arabic inscriptions often contained individual Songhay words in titles or names, like in the example below where the Songhay word is highlighted.

Hāđā al-qabr al-wazīr Muħammad Ariyaw ẓammu Kawkaw bin Būbakar "This is the tomb of Muhammad Ariyaw praise-named Kawkaw son of Boubacar." Fatima Kayna bint... "Little Fatima, daughter of..."

The older examples of Ajami are all notes taken by scribes in the margins of books written primarily in Arabic. Later, Fulfulde, Hausa, Wolof and Mandinke would use the script, with full books and poetry written in Ajami, and vast literary traditions emerging. By the 17th century, the script was being used to publish religious texts and poetry. Fulani poetry from the Futa Jallon region in Guinea was written in Ajami from the middle of the 18th century.

During the pre-colonial period, Qur'anic schools taught Muslim children Arabic and, by extension, Ajami. After Western colonization, a Latin orthography for Hausa was adopted and the Ajami script declined in popularity. Some anti-colonial groups and movements continued to use Ajami. An Islamic revival in the 19th century led to a wave of Ajami written works.

Ajami remains in widespread use among Islamic circles but exists in digraphia among the broader populace. Ajami is used ceremonially and for specific purposes, such as for local herbal preparations in the Jula language. In some areas of Ghana, Ajami is still seen in newspapers, advertisements, and daily life.