The new map erases one of Alabama's two constituencies with a black majority population, U.S. media reports.
The decision is the latest step in President Trump's fight to preserve the Republicans' narrow majority in the House of Representatives ahead of the November elections, and is seen as giving the party an important advantage in its bid to win seats from the Democrats.
Alabama's Republican governor took the case to the Supreme Court last week, after federal judges ruled that the map intentionally and unconstitutionally discriminated on the basis of race.
Several other states have previously voted to redraw their electoral districts, benefiting both Republicans and Democrats.
