Najib ad-Din Abu Hamid Muhammad ibn Ali ibn Umar Samarqandi (Arabic: نجيب الدين أبو حامد محمد بن علي بن عمر السمرقندي, ALA-LC: Najīb al-Dīn Abū Ḥāmid Muḥammad ibn ʿAlī ibn ʿUmar al-Samarqandī) was a 13th-century Persian physician from Samarqand.
Samarqandi died during the Mongol attack on Herat, in Afghanistan, in 1222CE. He was a prolific medical writer and expositor of medical ideas, though few details are known of his life.
His most famous book was The Book of Causes and Symptoms, a comprehensive manual of therapeutics and pathology. The treatises were widely read and often commentaries were written on them.