Kadhimiya (Arabic: ٱلْكَاظِمِيَّة, pronounced [alˈkaːðˤɪmijːa]) or Kadhimayn (ٱلْكَاظِمَيْن) is a northern neighbourhood of the city of Baghdad, Iraq. It is about 5 kilometres (3.1 mi) from the city's center, on the west bank of the Tigris. 'Kadhimiya' is also the name of one of nine administrative districts in Baghdad. As the place of al-Kadhimiya Mosque, even before its inception into the urban area of Baghdad, it is regarded as a holy city by Twelver Shia Muslims.

The neighborhood is home to families of upper class aristocratic class, as some of its people worked in goldsmith works and selling. Before the 14 July Revolution, Kadhimiya was inhabited by the parliament members of the royal era. Some of the popular politicians and leaders such as Muhammad Fadhel al-Jamali hailed from the region.

The Kāẓimayn ("Two who swallow their anger"), from whom the Mosque and area of Kadhimiyyah are named, are the Twelver Shia Imams Musa al-Kadhim and his grandson, Muhammad al-Jawad ibn Ali al-Ridha. The qubur (Arabic: قُبُوْر, graves) of the Kāẓimayn, and the scholars Mufid and Nasir al-Din al-Tusi, are within the premises of the Mosque. The area that now constitutes Al-Kāẓimiyyah was originally the location of a graveyard reserved for members of the Quraysh. This land was set aside for this purpose by the Abbasid caliph Harun al-Rashid. In its early history, the town was an important center of Shia learning, perhaps the main center, but over time the town declined, and other cities rose to prominence.

The location of the city has lent it to numerous plunders, that have resulted in damage to its shrines at different times in history. Among the most damage ever experienced by the town was after the Mongol Siege of Baghdad (1258) where the shrine of the Shia Imams was burnt down.

During the Government of Midhat Pasha in the Ottoman Empire, a tramway was built between Baghdad and Kadhiyma in order to transport the pilgrims who traveled to the Shia shrines. The tramway was in service until 1938 when bus services began to be established.

Baha'u'llah lived in this section of Baghdad during His exile from Iran, famously dictating the Hidden Words on the banks of the Tigris river. This makes the city significant for Baháʼí Faith.

The area was also an important center of Iraqi revolt against the British after World War I. The Al-Istrabadi family had friendly ties with the people of the royal government, such as Nuri al-Said. In 1941, 13 people were killed and more than 80 people were wounded in a demonstration against an attempt to demolish an old abandoned cemetery. During the 1958 coup by Abdul-Karim Qasim, when the government was toppled, Nuri al-Said sought refuge in the area. Muhammad Fadhel al-Jamali, who was from this neighborhood also sought refuge. Later they were captured.

In 2005, a stampede occurred on Al-Aimmah Bridge over the Tigris River. About 1000 people were killed. Iraqi officials executed Saddam Hussein at an American operated facility in al-Kāẓimiyyah known as "Camp Justice". The execution occurred on the occasion of Eid al-Adha, which attracted global widespread international criticism, even from Saddam's opponents.