John Silly was an English politician who sat in the House of Commons in 1659 and 1660.
Silly was the second son of John Silly (died 1646) of Trevelver, Cornwall and his first wife Elizabeth Marke, daughter of John Marke of Street Wenn.
His father, an attorney, had altered his name and arms from Ceely to Silly. In 1660, he was re-elected Member of Parliament for Bodmin in the Convention Parliament. Silly married Jane Cotton, daughter of William Cotton, precentor of Exeter Cathedral.
In 1659, Silly was elected Member of Parliament for Bodmin in the Third Protectorate Parliament.