The rally is against the social policies of the Moscow city government, and will take place in the centre of the Russian capital from 5:00 p.m. to 6:30 p.m. (13:00-14:30 GMT).
The protestors' main grievances are the administration's "irresponsible" construction policies and "illegal evictions."
A number of opposition parties are to take part. City authorities have set the limit of protesters at 500.
"The safety of the event will be ensured by 380 police officers. The police are prepared, within the law, to ensure order during the rally," the representative said.
A leader of one of the opposition groups set to take part, the Avangard Krasnoi Molodyezhi movement (Advance Guard of the Red Youth), said that the opposition would demand the dismissal of the Moscow administration.
"The policies being carried out by the administration [of Moscow] are making the city almost unfit to live in," Sergei Udaltsov said.
He also said that the rally would also see the participation of trade unionists as well as members of environmental and housing groups.
