The bustling city state now has 1.4 million vehicles for a population of 2.4 million, equivalent to 540 for every 1,000 people, according to the Roads and Transport Authority figures.
That compares with 305 vehicles per 1,000 people for New York and 213 per 1,000 for London.
The number of registered vehicles has risen from just 740,000 in 2006, an average annual increase of 8.2 percent.
If that trend continues, the number of vehicles registered could reach 2.2 million by 2020, when the emirate is due to host the five-yearly world trade fair, Expo.
Dubai has invested heavily in public transport infrastructure in recent years, opening a metro rail network in 2009 and the first phase of a tram network last year.
But car remains king and, despite massive road expansion projects, traffic jams are frequent.