Peterman, Buffalo's fifth-round draft choice out of Pittsburgh, completed 9 of 11 passes for 81 yards in two series, helping the Bills build an early 10-0 lead on the way to their first preseason victory.
Both teams rested several starters and had third-stringers in the game before the end of the first half.
Jonathan Williams had a 21-yard touchdown run in the first quarter for the Bills and finished with 53 yards on 10 carries. Joe Banyard rushed for 14 times for 68 yards and a 1-yard touchdown. Jordan Johnson had a 2-yard touchdown run in the fourth quarter.
Quarterback Jake Rudock played the entire first half for the Lions, completing 6 of 9 passes for 41 yards, and appears to have secured the backup job behind starter Matthew Stafford. Rookie Brad Kaaya was 12 of 20 passing for 182 yards and two touchdowns, but also threw an interception and lost a fumble.
Undrafted rookie Tion Green took a short pass from Kaaya for a 74-yard touchdown late in the fourth quarter and led the Lions in rushing with 63 yards on eight carries. Kaaya also connected with undrafted rookie Dontez Ford for a 6-yard touchdown in the closing minutes. Matt Asiata started at running back and rushed 11 times for 29 yards.
Matt Parter kicked a 53-yard field goal to make it 13-3 just before halftime.
Buffalo's Stephen Hauschka made field goals form 30 and 45 yards in the first half.
Journeyman Keith Wenning was 5 of 15 passing for 41 yards for Buffalo. Before Wenning was signed Monday, Peterman was the Bills' only healthy quarterback, with starter Tyrod Taylor and backup T.J. Yates in concussion protocol. Through the first three preseason games, Peterman completed 50 percent of his passes for 372 yards.
Both teams got out of the game without any key players being injured. The Bills lost backup right tackle Michael Ola (ankle) and defensive tackle Jerel Worthy (possible concussion) in the first half, while Lions backup right tackle Cornelius Lucas (ankle) left in the third quarter and did not return.
The Bills and Lions have met in the preseason finale every year since 2002. The Lions had won the previous nine matchups.