Xinhua News Agency said she opened her eyes Tuesday after having been unconscious since the fall.
"Her eyes opened slightly this morning, and she called out to her mom and dad when they entered the ward," Dr. Zhang Chenmei of Zhejiang Provincial Children's Hospital was quoted as saying. He added that the child made eye contact with her parents during their 30-minute meeting.
The girl, named Zhang Fangyu but known by the nickname Niu Niu, was in critical condition with serious internal injuries when she was taken to hospital.
Zhang said that her heartbeat, blood pressure and pulse were now normal and "we can assume she's out of danger."
Earlier reports said Niu Niu was in the care of her grandmother when the older woman left the 10th-floor apartment outside the city of Hangzhou to run an afternoon errand.
Neighbors saw Niu Niu dangling from the apartment window for several minutes before she fell. A 31-year-old mother, Wu Juping, ran to catch the child and saved her from hitting the ground.
The impact knocked Wu out and she fractured her arm.