The Lachish reliefs are a set of Assyrian palace reliefs narrating the story of the Assyrian victory over the kingdom of Judah during the siege of Lachish in 701 BC. Carved between 700 and 681 BC, as a decoration of the South-West Palace of Sennacherib in Nineveh (in modern Iraq), the relief is today in the British Museum in London, and was included as item 21 in the BBC Radio 4 series A History of the World in 100 Objects by the museum's former director Neil MacGregor. The palace room, where the relief was discovered in 1845–1847, was fully covered with the "Lachish relief" and was 12 metres (39 ft) wide and 5.10 metres (16.7 ft) long. The Lion Hunt of Ashurbanipal sequence was found in the same palace.

The reliefs were discovered by the then 28-year-old Austen Henry Layard during excavations in 1845–1847. Commenting on the inscription above the seated figure of Sennacherib, Layard wrote:

Here, therefore, was the actual picture of the taking of Lachish, the city as we know from the Bible, besieged by Sennacherib, when he sent his generals to demand tribute of Hezekiah, and which he had captured before their return; evidence of the most remarkable character to confirm the interpretation of the inscriptions, and to identify the king who caused them to be engraved with the Sennacherib of Scripture. This highly interesting series of bas-reliefs contained, moreover, an undoubted representation of a king, a city, and a people, with whose names we are acquainted, and of an event described in Holy Writ.

— Austen Henry Layard, Discoveries Among the Ruins of Nineveh and Babylon, 1853,

Layard noted in his work that Henry Rawlinson, the "Father of Assyriology", disagreed with the identification as the biblical Lachish. Rawlinson had written in 1852: "At the same time, it is hardly possible that the capture of Lakitsu, which is figured in the most elaborate manner on the walls of Sennacherib's palace at Nineveh, can refer to this city, as the two names are written quite differently in the Cuneiform characters." Layard and others refuted Rawlinson's identification, and the identification as the biblical Lachish prevailed.

Israeli researcher Yigael Yadin showed that the images of the walls and town depicted fit with the uncovered walls and town as seen from a certain point near the Tel Lachish digs. The descriptions shown in the reliefs were compared with those written about Lachish in the bible and found to be similar as well.

The Lachish reliefs represent "the most elaborate set of reliefs depicting a siege of a city" produced by any Assyrian monarch. According to archaeologist David Ussishkin, while the artistic style follows the schematic traditions of the Neo-Assyrian Empire, the reliefs provide an uncharacteristically detailed view of the city's fortification and the exile of its inhabitants.

The narrative structure of the relief series is divided into two distinct temporal phases that meet at Lachish's central city gate: the military assault is depicted on the left, while the right side shows the removal of booty and the deportation of Lachish's residents. The artist utilized a specific spatial hierarchy where the city structures and siege ramp are rendered on a smaller scale compared to the human figures on either side, thereby focusing the viewer's attention on the fate of the people.