This research paper presents a study of a unique Mamluk memorial dinar minted in Damascus in 740 AH with the name of Sultan al-Nasir Muhammad Ibn Qalawun, weighing 29.8 grams and having a diameter of 30 mm in the collection of Professor Firas Abu Yahya in the United Arab Emirates. It has not been published or studied yet. This memorial dinar was minted in commemoration of the ascending the throne by the Abbasid Caliph al-Wathiq Bi-llah Ibrahim Ibn Muhammad Ibn al-Mustasik Ibn Ahmed Al-Hakim bi-Amr Allah in Egypt. The general form of this dinar was described in an accurate scientific manner, illustrating its writings and decorations, interpreting these writings in light of the different circumstances of Sultan al-Nasir Muhammad, and determining the reasons for minting this dinar. After that, memorial coins were discussed, and their differences from circulating coins were determined. Then, a comparison was made between the dinar understudy and a circulating dinar minted in the same mint, i.e., Damascus, and with the same date, highlighting their similarities and differences. Therefore, this research is an addition to Islamic memorial coins, especially those of Sultan al-Nasir Muhammad.