The body was ferried to Delhi in a chartered Air India plane AIC-380A that took off around 12:30 AM local time (10:00 PM IST), Indian High Commission officials said.
The girl, who was shifted here on December 27 from the Safdarjung Hospital in Delhi, breathed her last at 4:45 AM (2:15 AM IST), at Singapore's Mount Elizabeth Hospital, where she was treated.
On the chartered plane, sent here by the Indian government, were her family members who have been in Singapore since the girl was brought to the hospital here in an extremely critical condition.
The victim, who underwent three surgeries at Safdarjung Hospital, was gang-raped and brutally assaulted on December 16 by six men in a moving bus in Delhi. The assault had damaged her internal organs. She also suffered a cardiac arrest and brain injury.
"We are very sad to report that the patient passed away peacefully at 4.45 AM on 29 Dec 2012 (Singapore time)," the Singapore hospital's Chief Executive Officer Dr Kelvin Loh said in a statement.
"Her family and officials from the High Commission of India were by her side. The Mount Elizabeth Hospital team of doctors, nurses and staff join her family in mourning her loss," the statement said.
Indian High Commissioner T C A Raghavan told reporters that the girl, who was conscious, fought a brave battle till the end.
He said the final few hours was a trying time for the girl's family and they bore the entire process with a great deal of fortitude and courage.