She was conscious during her extraction just after midnight (16:00 GMT Wednesday) and advised rescuers how to bring her out safely, state media say.
Ten people are known to have survived but the death toll rose from five to 26 after more bodies were found.
Arrests have been made as the building’s safety is investigated.
Weak safety and construction standards, along with corruption among local officials, have led to a number of building collapses in China.
Rescuers in Changsha used traditional methods to detect signs of life – shouting, knocking and sniffer dogs – as well as drones.
The survivor brought out early on Thursday had spent about 132 hours trapped in the debris.
Another woman who was rescued after 88 hours has described how she kept herself alive by rationing drinking water and staying warm.
The unnamed 21-year-old was in bed when the rear of the building, which contained flats and businesses, caved in last Friday afternoon.
She fell four floors but the walls did not completely collapse and formed a triangle above her head, the Global Times reports.
Half a pot of water was crucial to her survival. There was so little of it she only drank one sip at a time, and some remained even by the time she was rescued. To keep warm, she wrapped herself in a quilt.
Her mobile phone lost signal after the disaster but she used it to keep track of the date and time, conserving the life of the battery so carefully that it was still working when she was found.
She used a hard object to knock on the wall next to her to signal for help. “I did not knock when I heard the noise outside, but I knocked regularly when I felt that the rescuers were close or it was quiet outside and I soon got a response,” she said.
The story of the “Changsha girl” has inspired people across China, where the collapse of the building has been one of the most trending stories on social media platform Sina Weibo.
Chinese President Xi Jinping ordered both an all-out rescue effort and a thorough investigation into the disaster.
At least nine people have been arrested. Four were charged with causing a major liability accident and five were accused of providing false documents.