Ursula Küper (later Stille, born 28 November 1937) is a retired German swimmer. In 1960, she set a world record in the 100 m breaststroke. The same year she competed at the 1960 Summer Olympics and won a bronze medal in the 4 × 100 m medley relay. Two years later she won a bronze medal in the 200 m breaststroke at the 1962 European Aquatics Championships. She finished eighth in this event at the 1964 Olympics.
Her stepdaughter Antje Stille competed in swimming at the 1976 Olympics; Küper is married to her father Peter Stille.