Emergency services were called to the blaze, which broke out in a ground-floor flat in Fairburn Street, Tollcross, at around 11pm on Monday.
One woman was rescued by firefighters from a top-floor flat in the four-storey block, while seven other people were treated for a range of injuries including smoke inhalation and head wounds.
At the peak of the blaze around 50 firefighters were in attendance. The cause is not known but fire and police officers will investigate once the scene is safe.
The Red Cross also helped at the scene to look after residents evacuated from their homes.
A Scottish Fire and Rescue Service spokesman said: “The service received a 999 call from a member of the public shortly before 11pm alerting them to a fire within the ground floor of the four-storey tenement building.
“Local fire crews from Clydesmill, Calton and Polmadie where immediately dispatched and on their arrival were met with a well-developed fire. The incident commander immediately requested further resources to deal with the fire and attend to casualties at the scene.
“Firefighters rescued one woman from the top-floor flat and are also working with the Scottish Ambulance Service in attending to eight casualties with injuries relating to smoke inhalation, head and physical injuries.
“A number of residents have been evacuated from the affected and neighbouring properties and the fire service have requested the attendance of the British Red Cross fire and emergency support service to assist in dealing with the evacuated residents.
“The service will be in attendance for some considerable time and, whilst their incident research and investigation unit is in attendance, the cause of the fire at this stage has yet to be determined.”