With a population of 2.95 million ( September 2004 census ) , Casablanca is Morocco 's biggest city . The 2004 census recorded a population of 2,949,805 in the prefecture of Casablanca and 3,631,061 in the region of Grand Casablanca . Casablanca is considered the economic and business center of Morocco , while the political capital city of Morocco is Rabat .