The 33-year-old was dragged into common close in Edinbeg Avenue, Toryglen and raped by three men.
Police said a man got out of a car - possibly a white or silver BMW - and forced the woman into doorway.
Two other men, who the victim believes were also in the car, then attacked her.
It happened between 12am and 3am on Saturday.
The gang made off and the victim managed to make her way home.
Although she did not require hospital treatment, the woman has been left "extremely distressed" by the incident.
Detective Chief Inspector Sharon MacGregor, said: "Extensive inquiries are taking place by a team of dedicated officers.
"We are carrying out door to door enquiries and checking all available CCTV in order to trace the men responsible for this assault.
"I would appeal to anyone who saw or heard a disturbance in Edinbeg Avenue in the early hours of Saturday to contact police.
"I would also ask anyone who saw three Asian men in a light coloured car, in the area around Edinbeg Avenue to contact officers."
A massive police operation is now underway to trace the attackers.
Police said the three suspects are described as Asian and in their 20's.
Chief Inspector Carol McGuire, said: "I would like to reassure the public that we have and will continue to have extra uniform patrols in the area.
"Anyone with any concerns should speak to an officer.
"A crime of this nature is very rare in what is a tight knit community."
Anyone with any information is asked to contact London Road Police Office on 101.