The River Hayle (Cornish: Heyl, meaning estuary) is a small river in West Cornwall, England, United Kingdom which issues into St Ives Bay at Hayle on Cornwall's Atlantic coast.

[1] The River Hayle is approximately 12 miles (19 kilometres) long and it rises south-west of Crowan village.

It then flows through a steep wooded valley north of the granite high ground at Trescowe Common, formerly a mining area, before turning abruptly north near the hamlet of Relubbus.

It then follows a northerly course for the remaining six miles to the estuary, passing St Erth.

[2] Areas around the estuary are designated as sites of special scientific interest (see also Hayle SSSI).