The City Medical Examiner has identified the woman as 45-year-old Ruth Deogracias of Wahiawa.
Emergency medical officials say they got the call around 1:45 Monday afternoon.
Police say she was found unresponsive in the ocean.
The woman was pulled out of the ocean but attempts to revive her were unsuccessful.
The woman was pronounced dead at the scene.
RELATED STORY: Schofield woman apparently drowns at Haleiwa Beach