The women had been trafficked and were mostly from Paraguay or Peru, according to city officials.
They say 57 raids took place over the past two weeks, leading to the arrests of 25 people.
The trafficking of young women has become a major concern in Argentina in recent years.
Thirty bars which had been seeking to "cheat the authorities and operate as brothels" had had their licences revoked, said deputy head of the city administration, Maria Eugenia Vidal.Drugs seized
Fake documentation and drugs were also seized during the raids, according to Guillermo Montenegro, Buenos Aires City justice minister.
"This doesn't only have to do with one crime, it's several crimes," he told reporters.
He also said some officials were themselves being investigated, without giving further details.
The investigation was triggered by a complaint by a neighbour at one of the locations in the Constitucion area of Buenos Aires.
The site's phone lines were then tapped, which led to the uncovering of a larger network, according to the Argentina's La Nacion newspaper.
In 2008, Argentina passed legislation that for the first time made human trafficking a crime. Thousands of victims have since been rescued.
That law followed a high profile campaign by Susana Trimarco, whose daughter Marita Veron went missing 11 years ago.
Campaigners say she was one of many victims abducted by sex rings that cater for powerful clients in Argentina.