Thomas Cocklyn was an English pirate of the Post Spanish Succession Period that was known for partnering with both Howell Davis and later Olivier Levasseur. He was elected captain in 1717 after sailing out of the pirate haven of Nassau on the island of New Providence in the British controlled Bahamas. Not much is known about his early life or much of his exploits in general.
It is known that on 1 April 1719 Cocklyn and his crew helped capture the Bird Galley, a British slave ship at the mouth of the Sierra Leone River along with Davis and La Buse. The account was documented by a William Snelgrave who recounted their month long party aboard his ship before they let him go aboard the Bristol Snow along with whatever cargo remained after the party. On 10 May 1719 the three pirate captains had a conflict with each other and went their own ways. Nothing more is known about Cocklyn and his career after 1719.