The Short Answer
Poseidon's parents are Cronus and Rhea. That's the standard Hesiod account from the Theogony, and it's what every textbook will tell you. Cronus was a Titan, Rhea was a Titaness. They were the second generation of divine rulers before Zeus overthrew them. But it's not that simple if you actually look at the sources.
Who Are Poseidon S Parents
Most people stop at Cronus and Rhea and consider that done. The issue is that ancient sources aren't always consistent, and there are fragments and local traditions that complicate the picture. I ran into this when someone asked me about a reference they'd seen where Poseidon's parentage was mentioned differently in a obscure scholion on a Pindar fragment. It wasn't a major alternative tradition, just a marginal note that some editor had included from a lost commentary. It made the conversation awkward because the "correct" answer suddenly depended on which text you were reading. The standard genealogy goes like this: Cronus and Rhea had six children, all swallowed at birth by Cronus because he'd been warned that one of them would overthrow him, just as he'd overthrown his own father Uranus. The children were Hestia, Demeter, Hera, Hades, Poseidon, and Zeus. Rhea tricked Cronus by giving him a stone wrapped in blankets instead of baby Zeus, and Zeus eventually forced his father to spit out all the siblings. Then they teamed up to take down the Titans. Poseidon ended up getting the sea as his domain when the three brothers drew lots after the Titanomachy. Zeus got the sky, Hades got the underworld, and Poseidon got the ocean. That's from the standard myth cycle.
There's one thing beginners usually miss here. People tend to think of Cronus and Rhea as the only parental figures for the Olympians, but in some regional cults and older fragmented traditions, there are references to other divine associations. The Homeric Hymn to Poseidon doesn't dwell on his parentage much because it's assuming the audience already knows it. That's the thing about these sources - they weren't written as reference material. They were written for people who already knew the myths and needed poetry or ritual context. Also worth noting: some later sources conflate Cronus with the Roman Saturn, and the genealogy gets muddled in Roman adaptation. If you're reading Ovid or later Latin poets, the parentage is the same on the surface but the cultural framing shifts. Saturn and Ops take the place of Cronus and Rhea, but the narrative structure stays basically identical. The main pitfall is assuming there's one single authoritative version. The mythological tradition is a collection of regional variants, poet disagreements, and later editorial syntheses. Cronus and Rhea is the answer you want for a quiz, a paper, or general knowledge. But if you dig into the actual primary sources, you'll find that the details around birth, naming, and early childhood vary enough that no single account is definitive.
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