John Haynes (May 1, 1594 - January 1653 or 1654) was a colonial magistrate, one time governor of the Massachusetts Bay Colony, and an eight-time governor of the Connecticut Colony.

John Haynes was born in Essex, England, a hotbed of the Puritan movement. He was the son of John Haynes and Mary Michel. He accumulated wealth and land in England, but left it all behind in July of 1633 to settle in the Massachusetts Bay Colony. Initially, he settled in Newtown, and as a prominent member of the colony, he was selected to serve one term as governor in 1635. Roger Williams was banished under his administration, though by latter accounts, Haynes grew to regret it.

Due to growing religious strife and food shortages in the colony, Haynes made the decision to take his family and set off with Thomas Hooker to form a colony in the area that would be known as Connecticut. After the ratification of the Fundamental Orders of the colony in 1638/9, Haynes was elected as the first governor of the Colony of Connecticut. He was apparently popular with the people of the colony, and there was no year that he was not either deputy governor or governor for the rest of his life. He died in January of 1634 or 1635, in Hartford.

His notable achievements include a part in the creation of the New England Confederation.

John Haynes was married to Mary Thornton, with whom he had six children. Several years after her death, he married Mabel Harlakenden, and they had five more children. One of John Haynes' children was General Hezekiah Haynes , a soldier in the army of Oliver Cromwell.