Mayfield threw for 334 yards and four touchdowns in the Browns' 41-35 win over the Titans. His quarterback rating of 147 was the second-best mark of his career.
Mayfield beat out Detroit's Matthew Stafford and Las Vegas' Derek Carr for the weekly honor.
Mayfield became just the second player in team history to throw four touchdown passes in the first half of a game. The other was Hall of Famer Otto Graham, who did it all the way back in Dec. 1951. Mayfield also passed Graham for most touchdown passes by a Browns player in his first three seasons (70).
On the season, Mayfield is completing 62.7 percent of his passes for 2,442 yards, 21 touchdowns and just seven interceptions. Mayfield hasn't thrown an interception in his last 156 throws, a stretch that dates back to the first quarter of the Browns' Week 7 win over the Bengals.