St. John's Regional Fire Department Supt. Don Byrne says two of the seniors were listed in critical condition.
He says 179 other residents of the Maplewood Apartments were taken by transit buses to city hall where they were to be met by family members.
Byrne says the fire broke out around 4 p.m. Wednesday in an apartment on the building's third floor.
He says although firefighters had it under control within 30 minutes, there was extensive damage to that part of the building.
The Royal Newfoundland Constabulary is investigating the cause of the blaze.