The five major cities, Dublin, Cork, Limerick, Galway, and Waterford, as a group have been losing population share compared with the rest of the country, according to the new Census figures from Central Statistics Office.
Figures show that the cities grew by only half the rate of the whole country in the four years between 2002 and 2006.
Galway city was the only exception to the trend with population growth of almost 10% in the four years.
Outside of the main cities, there was also a sharp growth in the population of large towns with 10,000 people are more.
The Census figures show the number of these towns has increased from 28 to 34 in the last four years; the six new large towns include Mallow, Wicklow, Arklow, Cobh, Midleton, and Ballina.
The figures also show that the population of Balbriggan in Co Dublin has grown by 51% in four years.
The data also reveals an extremely strong growth in the population of Blanchardstown-Blakestown electoral district of Dublin West, where the population has grown by 8,000 in three years and now stands at 32,300.
According to the Constitution, an additional TD may now be justified for the area.