Ħaġar Qim (Maltese pronunciation: [ˈħɐd͡ʒɐr ˈʔiːm]; lit. 'Worshipping Stones') is a megalithic temple complex found on the Mediterranean island of Malta, dating from the Ġgantija phase (3600–3200 BC). The Megalithic Temples of Malta are among the most ancient religious sites on Earth, described by the World Heritage Sites committee as "unique architectural masterpieces." In 1992 UNESCO recognized Ħaġar Qim and four other Maltese megalithic structures as World Heritage Sites. V. Gordon Childe, Professor of Prehistoric European Archeology and director of the Institute of Archaeology in the University of London from 1946 to 1957 visited Ħaġar Qim. He wrote, "I have been visiting the prehistoric ruins all round the Mediterranean, from Mesopotamia to Egypt, Greece and Switzerland, but I have nowhere seen a place as old as this one."

Ħaġar Qim's builders used globigerina limestone in the temple's construction. As a result of this, the temple has suffered from severe weathering and surface flaking over the millennia. In 2009, work was completed on a protective tent.

The megalithic complex of Ħaġar Qim is located on the southern edge of the island of Malta, on a ridge capped in soft globigerina limestone. Globigerina limestone is the second oldest rock on Malta, outcropping over approximately 70% of the area of the islands. The builders used this stone throughout the temple architecture. All exposed rock on the island was deposited during the Oligocene and Miocene periods of geological time.

The temple's façade is characterized by a trilithon entrance, outer bench and orthostats. It has a wide forecourt with a retaining wall and a passage runs through the middle of the building, following a modified Maltese megalithic design. A separate entrance gives access to four independent enclosures which replace the north-westerly apse.

Features of temple architecture reveal possible associations with fertility rituals, including corpulent figurines and statuary, together with solar alignments and a megalith which it has been argued is phallic. The presence of an altar with a concave top indicated a possible use for animal sacrifices. It has also been suggested that screened doorways at the heart of the complex point towards possible use by oracles. Excavation also uncovered decorated pottery. The best examples can be seen at The National Museum of Archaeology.

No burials exist in the temple or the area surrounding Ħaġar Qim, nor have any human bones been discovered in Maltese temples. Bones of numerous sacrificial animals have been found. It is theorized that the Ħaġar Qim complex was built in three stages, beginning with the 'Old Temple' northern apses, followed by the 'New Temple', and finally the completion of the entire structure.

A few hundred metres from the temple is one of the thirteen watchtowers built by Grand Master Martin de Redin, called Ħamrija Tower. A memorial to General Sir Walter Congreve, Governor of Malta from 1924 to 1927, is located nearby. The village of Qrendi is a further two kilometres (1.2 miles) southwest of the temple complex.

The Ħaġar Qim complex consists of a main temple and three additional megalithic structures beside it. The main temple was built between 3600 and 3200 BC; however, the northern ruins are considerably older. The outside entrance serves as an interior passage and connects six large chambers. The right apse is constructed as an arch to prevent the upright slabs falling inward. The outside wall, built of huge upright blocks, projects inwards, thus creating an extremely solid building. This entrance passage and first court follow the Maltese megalithic pattern but as building progressed, this design was considerably modified. The northwesterly apse was replaced by four independent enclosures.