James Corwin Mackey (born February 25, 1986) is an American professional poker player.

He attended the University of Missouri before dropping out of a pre-med program to pursue a career in professional poker.

In 2007, at 21 years and 4 months, Mackey became the third youngest poker player at the time to ever win a World Series of Poker bracelet, when he won the $5,000 buy-in No-Limit Hold'em event, behind Steve Billirakis (won a bracelet in the first event of the 2007 tournament) and Jeff Madsen (won a bracelet in the 2006 tournament).

[1] Mackey's near-record setting win (third youngest to win a bracelet), in the 2007 $5,000 buy-in No-Limit Hold'em event, came against a final table that included two players from the 2005 and 2006 Main Event, as well as two former bracelet winners.

[2] In the following year's tournament, Mackey finished runner-up in the $10,000 World Championship Mixed Event, earning $297,792.