The team managed to find the back of the net despite losing their match against Russia by 30 goals.
The women's team, formed just one month before the tournament, lost their game against Russia on Tuesday but celebrated their goal as if they had won the tournament.
They suffered a record 64-0 defeat against Hungary in their first game at the weekend before taking on 2017 bronze medallists Russia in the group round match.
All the players except captain Oh Hee-ji are still in their teens, and were chosen from former swimmers.
Goalscorer Kyung Da-seul said she felt “as if she had hit the winning run in baseball's World Series,” according to Channel News Asia.
She added: "When I took the shot I didn't think it was going to go in, but I gave it everything I had. I couldn't have done it without my teammates.
"Our coaches told us that we're here to show people that we're ready to battle hard.
"They also said we grew so much after the first game - we shed many tears of joy."
Korean-American Ryan Hanna Yoon promised there was more to come from the hosts, adding: "It was really emotional because we've been going through a lot.
"The goal means everything for us. We're just beginners in water polo.”