Ristoski, 31, is the first Croatian athlete to win medals at three successive Paralympic games.
In London in 2012, she won a bronze in this event, and in Rio de Janeiro in 2016, she became the Paralympic champion in the women's long jump event in her category.
In Tokyo, the gold in this event was taken by Polish Karolina Kucharczyk, while Aleksandra Ruchkina grabbed a silver.