Goals from Harrison Burrows and Ephron Mason-Clark early in both halves did the damage to earn a spot in the third round draw.
Our photographer David Lowndes took these pictures of fans braving the chilly weather to be at the game.
Take a look and see if you can spot a familiar face.
Get more Posh news, here.
Take a look and see if you can spot a familiar face.
9. Posh 2 Doncaster 1
Peterborough United fans watch the 2-1 FA Cup win over Doncaster Rovers. Photo: David Lowndes
10. Posh 2 Doncaster 1
Peterborough United fans watch the 2-1 FA Cup win over Doncaster Rovers. Photo: David Lowndes
11. Posh 2 Doncaster 1
Peterborough United fans watch the 2-1 FA Cup win over Doncaster Rovers. Photo: David Lowndes
12. Posh 2 Doncaster 1
Peterborough United fans watch the 2-1 FA Cup win over Doncaster Rovers. Photo: David Lowndes
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