Medeshamstede ( /miːdsˈhæmstɛd/) was the name of Peterborough in the Anglo-Saxon period. It was the site of a monastery founded around the middle of the 7th century, which was an important feature in the kingdom of Mercia from the outset. Little is known of its founder and first abbot, Sexwulf, though he was himself an important figure, and later became bishop of Mercia. Medeshamstede soon acquired a string of daughter churches, and was a centre for an Anglo-Saxon sculptural style.

Nothing is known of Medeshamstede's history from the later 9th century, when it is traditionally believed to have been destroyed by Vikings, until the later 10th century, when it was restored as a Benedictine abbey by Bishop Æthelwold of Winchester, during a period of monastic reform. Through aspects of this restoration, Medeshamstede soon came to be known as "Peterborough Abbey".

The name has been interpreted by a place-name authority as "homestead belonging to Mede".

According to the Peterborough version of the Anglo-Saxon Chronicle, written in the 12th century, this name was given at the time of the foundation of a monastery there in the 7th century, owing to the presence of a spring called "Medeswæl", meaning "Medes-well". However the name is commonly held to mean "homestead in the meadows", or similar, on an assumption that "Medes-" means "meadows".