- Ibn Wahbān, ʻAbd al-Wahhāb ibn Aḥmad, -1366 or 1367. Qaʼid al-sharāʼid wa-naẓm al-fawāʼid1
- Ibn al-Bārizī, Hibat Allāh ibn Najm al-Dīn, 1247-13381
- Ibn al-ʻImād al-Aqfahsī, Aḥmad, approximately 1349-1405. Manẓūmah fī al-najāsāt al-maʻfū ʻanhā1
- Ibn ʻAbd al-Razzāq, ʻAbd al-Raḥmān ibn Ibrāhīm, -1727. Qalāʻid al-manẓūm1
- Ibn ʻĀbidīn, Muḥammad Amīn ibn ʻUmar, 1783 or 1784-1836. ʻUqūd rasm al-muftī1
- Ibn Ḥajar al-Haythamī, Aḥmad ibn Muḥammad, approximately 1503-approximately 1566. Iʻlām bi-qawāṭiʻ al-Islām1
- Ijtihād (Islamic law)1
- Imaginary letters1
- Immortality--Islam1
- Imāmʹzādah, Muḥammad ibn Abī Bakr, 1097 or 1098-1177 or 1178. Shirʻat al-Islām1
- India--Hyderabad1
- Interest (Islamic law)1
- Interfaith relations1
- Iran--Ardabīl1
- Iran--Hamadān1
- Iran--Mashhad1
- Iran--Qum1
- Iran--Tabrīz1
- Iraq--Karbalāʼ1
- Irshād al-adhhān ilá aḥkām al-īmān (Ibn al-Muṭahhar al-Ḥillī, al-Ḥasan ibn Yūsuf)1