The 30-year-old Texan parred the final seven holes for a 4-under 68 and a two-stroke victory over Trey Mullinax and Sean O'Hair. Landry finished at 17-under 271 at TPC San Antonio.
Landry took a two-stroke lead to the par-5 18th after Mullinax chunked a flop shot and bogeyed the short par-4 17th. Landry hit a 55-foot putt over a ridge to 3 feet for par on 17 and made an 8-footer on 18 after running a 50-foot downhill birdie try past.
Mullinax closed with a 69 a day after breaking the AT&T Oaks Course record with a 62. O'Hair shot 66.
Tied for the third-round lead with Zach Johnson, Landry birdied the first three holes and added two more on Nos. 6 and 10. He bogeyed the par-4 11th before the closing par run.
Landry won in his 32nd PGA Tour start. He earned his tour card last year on the Web.com Tour, and lost a playoff to Jon Rahm in January in the CareerBuilder Challenge.
Landry played at Arkansas after starring at Port Neches-Groves High School east of Houston. He now lives in the Austin area.
