It was her second world title of the championships in South Korea, having also won the 200m freestyle on Wednesday.
She also picked up silver medals in the 200m IM and 200m backstroke and a bronze in the 400m IM.
Kula-Przezwanski was totally dominant in Saturday’s two length backstroke event, winning by more than eight seconds. She clocked 1:21.66, with Australia’s Vivienne Anthony taking second in 1:30.14.
Kula-Przezwanski, who also runs for Tavistock AC, is also a world age group aquathlon champion.