Peakirk is a civil parish in the city of Peterborough, Cambridgeshire in the United Kingdom. For local government purposes it forms part of Newborough ward; for parliamentary purposes it falls within Peterborough constituency. In 2001, the parish had a population of 321 persons and 139 households.

Saint Pega (died c. 719) the sister of Saint Guthlac of Crowland, had a hermitage here. The parish church is uniquely dedicated to St Pega and the name of the village is derived from "Pega's church". The church is a Grade I listed building and has a fine series of wall paintings. It is said that her heart was kept as a relic in the church, contained in a heart stone, the broken remains of which, smashed by Cromwell's troops, can be seen in the south aisle window.

The Wildfowl and Wetlands Trust, founded by Sir Peter Scott in 1946 to preserve and maintain Britain's many species of waterfowl, had a reserve here until 2001.