Ata Maama Tuutafaiva finished in first place with a winning throw of 15.60m.
Vahihina Doucet of French Polynesia scooped silver with a throw of 13.18m ahead of teammate Loveleina Wong-Sang, who scooped bronze with a throw of 12.32m.
Tonga is currently in 11th place with 1 gold and 1 bronze in the overall medal tally.
Leading in the games is Papua New Guinea with 12 gold, 7 silver and 4 bronze, ahead of Guam in second with 8 gold, 1 silver and 9 bronze.
Tahiti is currently in third place with 7 gold, 6 silver and 2 bronze medals.