Tyler Reed Duncan (born July 13, 1989) is an American professional golfer.

Duncan played his college golf for the Purdue Boilermakers.

Duncan played on the PGA Tour Latinoamérica in 2014 where his best finish was T-6 at the Lexus Panama Classic. In December 2014, Duncan finished in the top 45 at the Web.com Tour Qualifying Tournament earning his Web.com Tour card for 2015. He played on the Web.com Tour from 2015 to 2017. His best finish on the Web.com Tour was T-2 at the 2015 Brasil Champions and T-2 at the 2017 BMW Charity Pro-Am.

In 2017, he finished T-11 in the Web.com Tour Finals to earn his PGA Tour card for the 2017–18 season.

In November 2019, Duncan won the RSM Classic in a playoff over Webb Simpson. It was Duncan's first win in a multiple-day event since the 2011 Indiana Amateur. He did not win while playing college golf at Purdue and did not win at any level in professional golf. His win included his lowest round on tour, a second round 61.

Duncan's uncle, Andrew Johnson, is his swing coach. Johnson won the 2005 Cleveland Open on the Nationwide Tour.

PGA Tour playoff record (1–0)

Results not in chronological order in 2020.