The 49ers scored on their first five possessions and seven of eight in the game, with only a fumble marring their streak.
They won 37-24 for their fourth consecutive victory.
The 49ers improved to 10-4, while the Titans fell to 2-12.
San Francisco outgained Tennessee 430 to 306, going 9-of-15 on third down. Brock Purdy was 23-of-30 for 295 yards and three touchdowns. He threw a 4-yard score to Jauan Jennings, a 1-yarder to George Kittle and a 13-yarder to Jennings.
Purdy also lost a fumble.
Ricky Pearsall caught six passes for 96 yards but left late in the game with an undisclosed injury. Kittle caught eight passes for 88 yards and Jennings three for 37.
Christian McCaffrey had 22 carries for 73 yards and a touchdown.
The Titans hung tough, with Cam Ward completing 18 of 29 passes for 170 yards and two touchdowns. Defensive lineman Jeffery Simmons caught a 1-yard touchdown pass from Ward, and Gunnar Helm had a 34-yard score.
Tony Pollard rushed for 104 yards and a touchdown on 14 carries.
