William Hay, 4th Earl of Kinnoull

The Right Honourable The Earl of Kinnoull
Coat of arms of the Earls of Kinnoull
Personal details
Died	28 March 1677
Nationality	Scottish
Spouses	Lady Mary Brudenell (died 1665) Lady Catherine Cecil
Children	George Hay, 5th Earl of Kinnoull William Hay, 6th Earl of Kinnoull
Parents	George Hay, 2nd Earl of Kinnoull Ann Douglas

William Hay, 4th Earl of Kinnoull (died 28 March 1677) was a Scottish peer and soldier, loyal to King Charles I. He escaped twice from Edinburgh Castle.