The desperate rescue operation ended with the struggling whale swimming away from the ropes that were entangling it late on Friday morning after a long rescue operation.
The humpback swam straight towards the Sydney Heads and open ocean after being cut free.
Wildlife officers used a long pole to free the whale from the ropes and buoys that had become wrapped around its tale.
They earlier placed large orange buoys or kegs on the marine mammal, which was swimming between Bradley's Head and the Manly headlands, to hold it in place while NSW National Parks and Wildlife Service staff cut the animal loose.
Crews were monitoring the whale to ensure it was swimming freely, the service said.
The whale was first noticed by members of the public about 1pm on Thursday and reported to rescue organisation ORRCA's hotline.
The rescuers used buoys to keep the whale relatively still so they could free it from ropes. (Dan Himbrechts/AAP PHOTOS)
An ORRCA spokeswoman said the buoys had been used to help keep the whale relatively still while specialised staff worked to get it free.
"The whale has been going in circles in Sydney Harbour, making some erratic directional changes," she said in a video posted to Facebook.
"As you can imagine, it's a very, very difficult task to try and disentangle a whale.
"The crews on these vessels go through immense training and have to follow very tight procedures for the safety of not only the crew members but also the safety of the whale."