The demonstration moved from Place Victor Hugo to the Trocadero, drawing 2,000 participants, according to organisers.
Many carried pre-1979 Iranian monarchy flags bearing the lion and sun, chanting in support of the return of the former royal family under exiled crown prince Reza Pahlavi. Israeli and US flags were also visible among the crowd.
Speakers and protesters called for stronger international backing as unrest in Iran entered a third week.
Activists say at least 203 people have been killed during the demonstrations, though the toll may be higher. With internet access restricted inside Iran, those abroad fear the blackout is allowing security forces to intensify a violent crackdown with little scrutiny.
