The Australian woman who was killed in a crowd crush while celebrating Halloween in downtown Seoul has been identified as Grace Rached.

Ms Rached is the only confirmed Australian to die among more than 150 fatalities in the deadly crush.

The 23-year-old Sydneysider was working as a film production assistant for a company called Electriclime Films.

It is estimated that about 100,000 had gathered in the Itaewon neighbourhood in the South Korea capital on Saturday evening when people became trapped in a crowd crush. 

Her family released a statement saying they are "missing our gorgeous angel Grace who lit up a room with her infectious smile".

"Grace always made others feel important and her kindness left an impression on everyone she ever met," they wrote.

"Grace always cared about others and she was loved by all."

Her family said she was a talented film producer and passionate about making a difference.

"She cared deeply about her two sisters and was a wonderful role model," they said.

The family said they all deeply missed their "life of the party," and thanked everyone for their support before asking for privacy.