A group of around 200 masked anarchists smashed the windows of almost all of the shops along the main shopping street in the Greek capital during the night, police said on Tuesday.
"The pedestrianized Ermou (Hermes) Street has been devastated. The damage is enormous," Nikos Pararas, who owns a shoe shop on the street, told dpa.
Police said at least 60 shops had been damaged.
Before attacking the shops, the anarchists had marched to call for the release of a woman who had been sentenced to several years in jail for belonging to a left-wing terrorist organization.
On Monday, Greek judicial authorities had refused an application to have the woman released.
The destruction occurred in a matter of minutes, meaning the police were not on the scene fast enough to make arrests, state-run radio station ERT reported.
There is a large far-left anarchist scene in Greece which often launches violent protests. Their heartland in the Athens district of Exarcheia has been a no-go area for police for years.
The opposition accuses the left-wing government of Prime Minister Alexis Tsipras of turning a blind eye to the anarchists and of not doing enough to halt the disturbances they create.