John was the third son of John Cheyne (or Cheney) of Shurland Hall in Kent, by his wife, Eleanor, daughter and sole heiress of Sir Robert Shottesbrooke of Faringdon in Berkshire (now Oxfordshire). He was the uncle of Thomas Cheyne, Lord Warden of the Cinque Ports and grand-uncle of Tudor soldier and MP John Cheyne.
In the 1460s he was appointed Esquire of the body to Elizabeth Woodville, Queen of Edward IV, being made a Knight of the Bath at her coronation in 1465. From 1471 until 1481 he was MP for Wiltshire and in 1479 was appointed Master of the Horse. In the same year he married Margaret Chideock, eldest daughter of Sir John Chideock, and widow of William Stourton, 2nd Baron Stourton. Some sources say that they had a son who predeceased his father.
After the death of Edward, and the seizure of the crown by Richard III, Cheyne switched sides to support Henry Tudor's claim to the throne. He fought in 1485 at the Battle of Bosworth Field. When Richard III launched his last charge directly at Henry, Cheyne was part of Henry's personal bodyguard. Richard unhorsed him with a blow from his broken lance. He fought again at the Battle of Stoke in 1487. He was made a Knight of the Garter and was called to parliament as Baron Cheyne.
He lived at Faulston Cheyne in Wiltshire and Enborne in Berkshire. Nicknamed the "Vigorous Knight" by contemporaries, he was a massive man of redoubtable strength. A 21" thighbone, found in his tomb at Salisbury Cathedral in the 18th century, puts his estimated height at 6 feet 8 inches.
He had no surviving issue and the title died with him. His estates passed to his brother Robert.