The desperate search began yesterday when crew members were alerted to the situation on the Pacific Dawn cruise ship.
Searches for the woman have now been called off, authorities confirm.
The cruise liner spent hours yesterday circling in rough seas while staff scoured the ocean for the woman.
The ship remained in the area this morning to continue the search.
The Captain this morning made an announcement to passengers confirming the search had been unsuccessful.
'It is with a very heavy heart that I need to let you know that we have been unable to locate our guest,' he said, according to The Courier Mail.
'We are still in the area of the incident, and the weather conditions with the swell three to four metres high, as you can see outside...the strong wind made our search extremely challenging.'
'As a result we have now made the extremely difficult decision to continue our journey towards Brisbane.
'I know I speak on behalf of all of you when I say our thoughts and prayers are with the family.'
Passengers say her husband saw her fall and went into shock. Life rings were immediately thrown into the water, but there was no sign of her.
Other passengers said children that were near her also witnessed the devastating fall. The woman was believed to be travelling with her children, but it is unclear if they were on the deck with her.
'She leaned over and the ship rocked in heavy seas — her husband tried to catch her but she slipped,' one passenger posted to social media.
Passengers believe she may have been playing bingo before the tragedy as a woman was heard to say she was going outside because she was unwell. They then heard the alarm being sounded and the woman never returned.
More details to come.
This article originally appeared on New Idea.