A Qatari government official said the evictions are unrelated to the World Cup and were designed "in line with ongoing comprehensive and long-term plans to re-organize areas of Doha."
The Qatari official said municipal authorities have been enforcing a 2010 Qatari law which prohibits "workers' camps within family residential areas" - a designation encompassing most of central Doha - and gives them the power to move people out.
A Reuters reporter saw more than a dozen buildings where residents said people had been evicted. Some buildings had their electricity switched off.
The majority of the workers are Asian and African, and they claimed that more than a dozen buildings had been evacuated and shut down by officials, forcing them to find any refuge they could, even camped out on the sidewalk outside one of their old houses.
This comes as there are less than four weeks until the start of the world soccer championship on November 20, which has brought Qatar's treatment of foreign workers and its tight social restrictions to the public's notice.
At one building which residents said housed 1,200 people in Doha's Al Mansoura district, authorities told workers at about 8:00 pm on Wednesday they had just two hours to leave.
Municipal officials returned around 10:30 pm, forced everyone out and locked the doors to the building, they said. Some men had not been able to return in time to collect their belongings.
World soccer's governing body FIFA did not respond to a request for comment and Qatar's World Cup organizers directed inquiries to the government.
Most were in neighborhoods where the government has rented buildings for World Cup fan accommodation. The organizers' website lists buildings in Al Mansoura and other districts where flats are advertised for between $240 and $426 per night.
Some of the evicted workers said they hoped to find places to live amid purpose-built workers' accommodation in and around the industrial zone on Doha's southwestern outskirts or in outlying cities, a long commute from their jobs.