Sea turtle migration is the long-distance movement of sea turtles (superfamily Chelonioidea), comprising the swimming of adults to their breeding beaches, and also the offshore migration of hatchings. Sea turtle hatchings emerge from underground nests and crawl across the beach towards the sea. They then head offshore to the open sea. The feeding and nesting sites of adult sea turtles may be far apart, requiring some to migrate hundreds or even thousands of kilometres.
Several patterns of adult migration have been identified. Some green sea turtles shuttle between nesting sites and coastal foraging areas. The loggerhead sea turtle uses a series of foraging sites. Others such as the leatherback sea turtle and olive ridley sea turtle do not keep to one coastal foraging site, but forage in different areas in the open sea. Although the leatherbacks seem to forage randomly, drifting passively with the currents, they still return to specific sites to breed. The ability of adult sea turtles to travel to precise locations has led biologists to wonder about their navigational mechanisms. Some have suggested that turtles might use the Earth's magnetic field to fix their position. There is evidence for this ability in juvenile green sea turtles.