Peterborough's big-money recruit George Boyd scored one and created another as they recorded back-to-back wins for the first time this year.
Boyd, a £260,000 buy from Stevenage, put Posh in front after 51 minutes beating keeper Saul Deeney with a powerful finish from close range.
Boyd then turned provider four minutes later for Wales defender Craig Morgan.
He scored his first goal for the club with a header from the right of the area after good work by Boyd.
Peterborough: Tyler, Newton, Morgan, Futcher, Blackett, Low, Strachan (Butcher 90), Hyde, Gain, Boyd, Mackail-Smith (Crow 78).
Subs Not Used: Jalal, Day, Huke.
Goals: Boyd 51, Morgan 55.
Notts County: Deeney, Silk (Martin 65), Edwards, Hunt, McCann, Pipe, Somner, Smith, Parkinson (N'Toya 65), Dudfield, Mendes.
Subs Not Used: Pilkington, Sheridan, Gleeson.
Ref: K Hill (Hertfordshire).