Hilda Lorna Johnstone (4 September 1902 – 18 May 1990), more commonly known as Lorna Johnstone, was an Olympic equestrian specialising in dressage who represented Great Britain in three Summer Olympic Games. She was born in York.
She participated in the 1956, 1968 and 1972 Olympic Games where, aged 69, she became the oldest ever British competitor to appear in the Olympic Games. Her best finish was 5th place in the 1968 Mixed Dressage Team event.