Australia's Dani Samuels finished second (64.10m) and Briton Jade Lally third (61.65m).
Perkovic broke the 26-year-old meeting record held by Ilke Wyludda of Germany (68.04m).
After five out of seven competitions, Perkovic leads with a maximum 50 points ahead of German Nadine Mueller (14 points) and Cuban Denia Caballero (12 points).