Dianne de Leeuw was born in California to a Dutch mother and father with both Dutch and US citizenship. Her grandfather expressed a wish that she would run for the Netherlands, which, although she had spent most of her youth in the United States, she did.
On her first attempt, de Leeuw became Dutch champion in 1971, a title she was to defend until 1976. In 1971 she played her first European championship and a year later her first world championship and her first Olympic Games . Her breakthrough came in 1974. In Zagreb she became vice European champion behind Christine Errath from the GDR. At the World Championships in Munich , she won the bronze medal behind Errath and the American Dorothy Hamill . The following year, she was again Vice European Champion behind Errath in Copenhagen . The high point of her career came at the World Championships in Colorado Springs . There she clearly won the gold medal ahead of Hamill and Errath, which was dubiously received in the American press. The 1976 Olympic year, the last of her career, started well for de Leeuw. In Geneva she was the first European champion , ahead of the GDR runners Anett Pötzsch and Christine Errath. Then the Dutch press saw her as Sjoukje Dijkstra's successor . She had already been voted Dutch Sportswoman of the Year in 1975. At the World Cup in Gothenburg , however, she could not defend her world title. She won bronze behind Hamill and Errath. Even at the Olympic Games in Innsbruck , where she was the flag bearer of the Netherlands, she did not remain flawless and won the silver medal behind Hamill.
After the end of her amateur career, she went to an ice revue in 1976 and toured with it through North America. She later married her former trainer Doug Chapman and also became a trainer.