William de Grey (21 October 1652 - 27 February 1687) of Merton Hall, Norfolk was an East Anglian landowner and Tory Member of Parliament.
The descendant of Suffolk landowners who had acquired a seat at Merton, Norfolk by marriage in the 14th century, he was the only son of James de Grey (died 1665) and Elizabeth Stutevile, daughter of Sir Martin Stutevile of Dalham in Suffolk.
In 1676 he also became deputy lieutenant for Norfolk and a year later a major in the foot militia, holding both offices until his death.
He followed up these offices with a political career, successfully contesting Thetford in 1685 and proving quite active during James II's parliament.
He took part in committees considering bills on repairing Great Yarmouth pier, relieving imprisoned debtors, improving tillage and increasing the then-low prices on corn and wool, which were major local issue in East Anglia.