Tantalus is a Greek mythological figure who is bound in a pool of water in Tartarus, forever thirsty but never able to drink.

Tantalus may also refer to:

• Tantalus, son of Thyestes, killed, along with his brother Pleisthenes, by his uncle Atreus, father of Agamemnon
• Tantalus, one of the Niobids, children of King Amphion of Thebes and Niobe, daughter of Tantalus.

• 2102 Tantalus, an asteroid
• Mount Tantalus, southwestern British Columbia, Canada
• Tantalus Bluffs, Dufek Coast, Antarctica
• Tantalus Formation, a Mesozoic geologic formation
• Tantalus (Oahu), a peak on the Hawaiian island of Oʻahu
• Tantalus Peak, Victoria Land, Antarctica
• Tantalus Range, a mountain range in southwestern British Columbia

• Tantalus, a prison colony in the 1966 Star Trek episode "Dagger of the Mind"

• Abisara tantalus, a butterfly of the family Riodinidae
• Aellopos tantalus, a moth of the family Sphingidae
• Lepidochrysops tantalus, a butterfly of the family Lycaenidae
• Mecyclothorax tantalus, a ground beetle of the family Carabidae
• Tantalus monkey (Chlorocebus tantalus), a species endemic to Ghana, Sudan, and Kenya

• "The Torment of Tantalus" (Stargate SG-1), a 1997 TV series episode
• Tantalus, A 1999 play written by John Barton and directed by Peter Hall

• USS Tantalus (ARL-27), a United States Navy landing craft repair ship of World War II
• HMS Tantalus (P318), a British T-class submarine of World War II

• Tantalus (cabinet), a cabinet for displaying decanters but securing their contents
• Tantalus Media, an Australian video game development studio

• All pages with titles beginning with Tantalus
• All pages with titles containing Tantalus
• Tantalum (element "Ta"), a metallic element
• Tantalis
• Tantalize (disambiguation)