Michael Fien McCarthy (pictured) absconded from HMP Sudbury overnight between 17th and 18th June, a Derbyshire police spokesman said.
McCarthy (24) was convicted at Nottingham Crown Court last September to three years for wounding with intent.
He is white, 5 ft 11 inches tall, of medium build, with short blond hair and blue eyes. He speaks with an Irish accent.
People are being warned not to approach him and anyone with information is asked to immediately contact their local police or Crimestoppers anonymously 0800 555 111.