Shapshu (Ugaritic: 𐎌𐎔𐎌 špš, "sun") or Shapsh, and also Shamshu, was a Canaanite sun goddess. She also served as the royal messenger of the high god El, her probable father. Her most common epithets in the Ugaritic corpus are nrt ỉlm špš ("Shapshu, lamp of the gods", also translated as "torch" or "luminary" of the gods by various authors), rbt špš ("great lady Shapshu"), and špš ʿlm ("eternal Shapshu"). In the pantheon lists KTU 1.118 and 1.148, Shapshu is equated with the Akkadian ^dšamaš.

The original name of the goddess contained the consonant /m/, and this consonant appears in some of the Amorite theophoric names mentioning the goddess. In the Middle Bronze Age Alalah, a process of devoicing and denasalization of the consonant /m/ made it, as a result, a /p/; this process is only attested at Middle Bronze Age Alalaḫ and at Late Bronze Age Ugarit. While name in Alalah show a mixture of the forms (Shamshu and Shapshu), in Ugarit there is not one attestation, syllabic or alphabetic, to the form "Shamshu".

There is one attestation, from Alalah, of the form "Shamash" for the name of the Amorite solar deity.

Unlike Shamash or Utu in Mesopotamia, but like Shams in Arabia, Shapshu was a female solar deity. In addition to attestations in Ugaritic texts, Amarna letter EA 323 uses the Sumerogram for the sun deity, ^dUTU, as a feminine noun (ša ti-ra-am ^dUTU, line 19); given the letter's provenance with Yidya of Ashkelon it may refer to Shapshu. Similarly, the letter EA 155 from Abimilki of Tyre to the Pharaoh includes a feminine ^dUTU (LUGAL ^dUTU darītum, lines 6, 44). Old Akkadian names such as Tulid-Šamši (Šamaš-gave-(me-)birth) and Umma-Šamaš (Šamaš-is-my-mother) might indicate a female sun goddess tradition in 3rd millennium BCE Mesopotamia, derived from a Northwest Semitic solar goddess.

A pair of solar deities were worshipped at Ebla, whose names were written using Sumerograms: ^dUTU and his consort ^dUTU.SAL. The native Eblaite names for these deities remain unknown, though the Iron Age Aramaic Sefire steles refer to the consort of Samaš as Nur(u) ("luminary"), possibly corresponding to nrt ỉlm špš, the most common epithet of Shapshu. No theophoric names referring to Shapshu are known from Ebla; the individual whose name was translated by Pettinato as Ibbi-Sipish is now considered to be translated more accurately as Ibbi-Zikir, with Zikir being a deity unknown outside of theophoric names.

Shamshu (or Shapshu in the area of Alalah) was the Amorite solar deity.

Some names in the Execration texts mention Shamshu, not necessarily as a female deity ("š-m-šw ì-p-ì-ìrì-m" (*šamšu-ʾab(u)-ʾilim) - Šamšu is father of the gods; "š-m-šu ìri-m" (*šamšu-ʾilima) - Šamšu is god).

While at least one deity is known under the Sumerogram ^dUTU at Emar, their native name, gender, and affiliations to other Syrian deities remain unclear.