John Belasyse, 1st Baron Belasyse (or Bellasis) PC (24 June 1614 – 10 September 1689) was an English nobleman, Royalist officer and Member of Parliament, notable for his role during and after the Civil War. He suffered a long spell of imprisonment during the Popish Plot, although he was never brought to trial. From 1671 until his death he lived in Whitton, near Twickenham in Middlesex. Samuel Pepys was impressed by his collection of paintings, which has long since disappeared.