John Grey (c. 1523 – 1564) was an English courtier. He was condemned to death for his involvement in Wyatt's rebellion against Mary I, but was released under attainder. He was restored from attainder by Mary's successor, Elizabeth I, who also granted him the royal palace at Pirgo.  Lady Catherine Grey, his niece, and sister to Lady Jane Grey, was released into his care in 1563. He was again imprisoned for a short time after the publication of a book claiming that Catherine was the legitimate heir to the throne.