Ningal (written 𒀭𒊩𒌆𒃲, ^dNIN.GAL; in Sumerian: "Great Queen"; in Akkadian: Nikkal) was a Mesopotamian goddess regarded as the wife of the moon god, Nanna/Sin. She was particularly closely associated with his main cult centers, Ur and Harran, but they were also worshiped together in other cities of Mesopotamia. She was particularly venerated by the Third Dynasty of Ur and later by kings of Larsa.

Ningal's name has Sumerian origin and can be translated as "Great Queen". While she was a major deity in the Mesopotamian pantheon and the worship of her is attested from all periods of history of Mesopotamia, her character was largely "passive and supportive" according to Joan Goodnick Westenholz. She was the tutelary deity of Ur. She shared it with her husband Nanna (Akkadian Sin). She was referred to as the "lady" (NIN; Early Dynastic sources) or "mother" (AMA; Ur III sources) of Ur. She and the city could be compared to a mother and her child in literary texts. She was portrayed mourning over it in laments, such as Lament for Ur or Lament for Sumer and Ur.

Based on some of Ningal's epithets it has additionally been proposed that she was in part an astral deity, much like her husband. This aspect might have been reflected in titles such as Ninantagal, Ninmulnunna, Si-iminbi and possibly Kalkal, respectively "high lady", "lady, star of the prince", "sevenfold light" and "treasured".

Ningal's iconography was not consistent. It has been proposed that she could be represented as a seated goddess accompanied by the lunar crescent, a symbol of her husband. A type of bird, u₅-bi₂, was possibly associated with her, though the evidence is inconclusive. Proposed identities of this animal include the greylag goose and the whooper swan, but it is assumed that even in Ur, statues of a goddess accompanied by a water bird of the genus Anserini, well known from excavations, were more likely to represent Nanshe. Ningal was also called zirru, a term which might designate a female bird. Some en priestesses of Nanna, especially Sargon's daughter Enheduanna, were also referred to as zirru. On the Ur-Nammu Stele, Ningal is depicted sitting in her husband's lap. This type of depictions was meant to display the intimate nature of the connection between the deities and highlight their ability to act in unison, and is also attested for Bau and Ningirsu.

In medical treatises the term "hand of Ningal" referred to an unidentified skin disease; analogous names of diseases are attested for various other deities, for example Sin, Adad, Shamash and Geshtinanna.

Ningal's mother was Ningikuga (Sumerian: "lady of the pure reed"), as attested in a balbale composition and in an emesal love song. This goddess could be identified as a consort of Enki. The god list An = Anum identifies her with Damkina directly, though in its Old Babylonian forerunner she is a separate deity in the circle of Enki. Ningikuga could also instead function as the name of a manifestation of Ningal, addressed as "the pure one who purifies the earth".

The lunar god Nanna (Akkadian Sin) was regarded as Ningal's husband. Her role as his wife is the best attested aspect of her character. Some of her epithets underlined her connection to him, for example Ḫegalnunna ("wealth of the prince"). A derivative of Ningal were regarded as married to other moon gods in Hurrian (Kušuḫ or Umbu), Hittite (Arma) and Ugaritic (Yarikh) sources. In all of the corresponding languages her name was rendered as Nikkal, similarly as in Akkadian. The best attested children of Ningal and Nanna were Inanna (Ishtar), who represented Venus, and Utu (Shamash), who represented the sun. The view that Inanna was a daughter of Nanna and Ningal is the most commonly attested tradition regarding her parentage. The poem Agushaya refers to Inanna as Ningal's firstborn child. Due to her identification with Ishtar, the Hurrian and Elamite goddess Pinikir is referred to as a daughter of Sin and Ningal in a text written in Akkadian but found in a corpus of Hurro-Hittite rituals. Further relatively commonly attested children of Ningal and Nanna include the goddesses Amarra-uzu and Amarra-he'ea, known from An = Anum, Ningublaga (the city god of Ki'abrig) and Numushda (the city god of Kazallu). In Neo-Assyrian sources from Harran Nuska was regarded as the son of Ningal and her husband. In a Maqlû incantation, Manzat (Akkadian and Elamite goddess of the rainbow) appears as the sister of Shamash, and by extension as daughter of his parents, Ningal and her husband.

An = Anum indicates that Ningal was believed to have a sukkal (attendant deity), though the reading of their name, ^dME^kà-kàME, remains uncertain. Richard L. Litke argued that the gloss is unlikely to point at an otherwise unknown pronunciation of the sign ME, and assumed that the deity in mention was named Meme, while an alternate version of the list had the name Kakka in the same line instead. Manfred Krebernik [de] proposes that this deity is identical with the divine messenger Kakka. Litke instead concluded that in this case Kakka should be understood as a deity elsewhere equated with Ninkarrak, distinct from the messenger god. A medicine goddess named Kakka, associated with Ninkarrak and Ninshubur, is attested in sources from Mari.