In the third case of its type, President Obama's Department of Justice filed a lawsuit against South Carolina's immigration law.
"The Constitution and federal law do not permit the development of a patchwork of state and local immigration policies throughout the country," the department said in a statement.
"South Carolina's law clearly conflicts with the policies and priorities adopted by the federal government and therefore cannot stand," it added.
The South Carolina law gives more power to police officers to check immigration status during traffic stops and arrests and creates a new law enforcement group to combat phony documentation.
The Obama administration has had mixed results so far in its previous suits against states, winning a case in Arizona that halted a controversial provision and losing in Alabama. Both suits are pending appeal.