Seal of the Prophets (Arabic: خاتم النبيين, romanized: khātam an-nabīyīn or khātim an-nabīyīn; or Arabic: خاتم الأنبياء, romanized: khātam al-anbiyā’ or khātim al-anbiyā) is a title used in the Qur'an and by Muslims to designate the Islamic prophet Muhammad as the last of the prophets sent by God.

The title is applied to Muhammad in verse 33:40 of the Qur'an, with the popular Yusuf Ali translation reading:

Muhammad is not the father of any of your men, but (he is) the Messenger of Allah, and the Seal of the Prophets: and Allah has full knowledge of all things.

— Qur'an 33:40

There is a difference among the schools of Qur'anic recitation regarding the reading of the word خاتم in verse 33:40 – it can be read as either khātim or khātam. Of the ten qirā’āt (readings, methods of recitation) regarded as authentic – seven mutawātir and three mashhūr – all read خاتم in this verse with a kasrah on the tāʼ (خاتِم, khātim) with the exception of 'Asim, who reads with a fatḥah on the tāʼ (خاتَم, khātam). The reading of al-Hasan, a shadhdh (aberrant) recitation, is also khātam.

The recitation that has become prevalent in most of the world today is Hafs 'an 'Asim – that is, the qirā’ah of 'Asim in the riwāyah (transmission) of his student Hafs.

In a well-known hadith reported by Abu Hurayrah, Jabir ibn Abd Allah, Ubayy ibn Ka'b, and Abu Sa‘id al-Khudri, and recorded by al-Bukhari, Muslim ibn al-Hajjaj, al-Tirmidhi, Ahmad ibn Hanbal, al-Nasa'i, and others, Muhammad compared the relationship between himself and the previous prophets to a building missing a single brick. In Sahih al-Bukhari it is reported by Abu Hurayrah that Muhammad said, "My similitude in comparison with the prophets before me is that of a man who has built a house nicely and beautifully, except for a place of one brick in a corner. The people go about it and wonder at its beauty, but say: 'Would that this brick be put in its place!' So I am that brick, and I am the seal of the prophets" (fa’anā ’l-labinah, wa anā khātamu ’n-nabīyīn). This hadith is narrated with similar wording in Sahih Muslim, Musnad Ahmad ibn Hanbal, as-Sunan al-Kubra of al-Nasa'i, and Sahih Ibn Hibban. In Mu'jam al-Awsat, al-Tabarani narrated a variant wording of the hadith with the last statement being, "So I am that [brick], I am the seal of the prophets, there is no prophet after me" (fa’anā dhālika, anā khātamu ’n-nabīyīn, lā nabīya ba‘dī). Ibn Hibban also has a variant ending with "I was the place of that brick, with me the [line of] messengers is sealed" (fakuntu anā mawḍi‘u tilka ’l-labinah, khutima biya ’r-rusul). In Sahih Muslim and Musnad Ahmad the hadith is also reported by Jabir ibn Abd Allah, with the last statement being "So I am the place of that brick, I have come and sealed the [line of] prophets" (fa’anā mawḍi‘u ’l-labinah, ji’tu fakhatamtu ’l-anbiyā’). Abu Dawud al-Tayalisi in his Musnad has from Jabir, "So I am the place of that brick, with me the [line of] prophets is sealed" (fa’anā mawḍi‘u ’l-labinah, khutima biya ’l-anbiyā’).

In another hadith, Muhammad prophesied the appearance of a number of false prophets before the day of judgement, while asserting his status as the seal of the prophets. It is reported by Thawban ibn Kaidad that Muhammad said, "The Hour will not be established until tribes of my ummah (community) unite with the idolaters, and until they worship idols. And in my ummah there will be thirty liars, each of whom will claim to be a prophet, (but) I am the seal of the prophets, there is no prophet after me." Hudhayfah ibn al-Yaman reports that Muhammad said, "In my ummah there will be twenty-seven liars and dajjals, among whom are four women, (but) I am the seal of the prophets, there is no prophet after me".