The Battle of Mu'tah (Arabic: مَعْرَكَة مُؤْتَة, romanized: Maʿrakat Muʿtah, or Arabic: غَزْوَة مُؤْتَة Ghazwat Muʿtah) took place in September 629 (1 Jumada al-Awwal 8 AH), between the forces of Muhammad and the army of the Byzantine Empire and their Ghassanid vassals. It took place in the village of Mu'tah in Palaestina Salutaris at the east of the Jordan River and modern-day Karak.

In Islamic historical sources, the battle is usually described as the Muslims' attempt to take retribution against a Ghassanid chief for taking the life of an emissary. According to Byzantine sources, the Muslims planned to launch their attack on a feast day. The local Byzantine Vicarius learned of their plans and collected the garrisons of the fortresses. Seeing the great number of the enemy forces, the Muslims withdrew to the south where the fighting started at the village of Mu'tah and they were either routed or retired without exacting a penalty on the Ghassanid chief. According to Muslim sources, after three of their leaders were killed, the command was given to Khalid ibn al-Walid and he succeeded in saving the rest of the force.

Three years later the Muslims would return to defeat the Byzantine forces in the Expedition of Usama bin Zayd.

The Byzantines were reoccupying territory following the peace accord between Emperor Heraclius and the Sasanid general Shahrbaraz in July 629. The Byzantine sakellarios Theodore, was placed in command of the army, and while in the area of Balqa, Arab tribes were also employed.

Meanwhile, Muhammad had sent his emissary to the ruler of Bostra. While on his way to Bostra, he was executed in the village of Mu'tah by the orders of a Ghassanid official Shurahbil ibn Amr.

Muhammad dispatched 3,000 of his troops in the month of Jumada al-Awwal 7 (AH), 629 (CE), for a quick expedition to attack and punish the tribes for the murder of his emissary by the Ghassanids. The army was led by Zayd ibn Harithah; the second-in-command was Ja'far ibn Abi Talib and the third-in-command was Abd Allah ibn Rawahah. When the Muslim troops arrived at the area to the east of Jordan and learned of the size of the Byzantine army, they wanted to wait and send for reinforcements from Medina. 'Abdullah ibn Rawahah reminded them about their desire for martyrdom and questioned the move to wait when what they desire was awaiting them, so they continued marching towards the waiting army.

The Muslims engaged the Byzantines at their camp by the village of Musharif and then withdrew towards Mu'tah. It was here that the two armies fought. Some Muslim sources report that the battle was fought in a valley between two heights, which negated the Byzantines' numerical superiority. During the battle, all three Muslim leaders fell one after the other as they took command of the force: first, Zayd, then Ja'far, then 'Abdullah. The leader of the Arab vassal forces, Mālik ibn Zāfila, was also killed in battle. After the death of 'Abdullah, the Muslim soldiers were in danger of being routed. Thabit ibn Aqram, seeing the desperate state of the Muslim forces, took up the banner and rallied his comrades, thus saving the army from complete destruction. After the battle, ibn Aqram took the banner, before asking Khalid ibn al-Walid to take the lead.

Four of the slain Muslims were Muhajirin (early Muslim converts who emigrated from Mecca to Medina) and eight were from the Ansar (early Muslim converts native to Medina). Those slain Muslims named in the sources were Zayd ibn Haritha, Ja'far ibn Abi Talib, Abd Allah ibn Rawaha, Mas'ud ibn al-Aswad, Wahb ibn Sa'd, Abbad ibn Qays, Amr ibn Sa'd, Harith ibn Nu'man, Suraqa ibn Amr, Abu Kulayb ibn Amr, Jabir ibn Amr and Amir ibn Sa'd.