Olympic traffic restrictions started on Sunday with the aim of reducing the number of vehicles on the streets and improving air quality in Beijing, the dpa reported.
Vehicles with even and odd licence plate numbers will be allowed onto the streets on alternate days in Beijing until September 20.
The Beijing Olympics take place August 8-24, followed by the Paralympics September 6-17.
The Xinhua news agency reported that Beijing authorities expect around 2 million vehicles off the streets, including those banned earlier for not meeting emission standards.
The Chinese capital with a population of 17 million has some 3.3 million vehicles. Many locals are now expected to switch to public transport, with three new subway lines opened on the weekend in a major Olympic infrastructure programme.
Improved air quality is an expected important side effect in the measures for the Olympics.
Beijing's notorious pollution has led to concern around Olympic competition and the International Olympic Committee has already said it will reschedule endurance events if the air quality is too bad.