German Chancellor Angela Merkel is the most powerful woman in the world, according to the magazine.
Forbes calls Merkel the European Union's undisputed leader. She was at the top of the list from 2006 to 2009.
Merkel was awarded the Presidential Medal of Freedom in Washington in June, but despite the string of international accolades, Merkel faces a drop in popularity among voters and her party in Germany.
Secretary of State Hillary Clinton came in second on this year's list, and Brazilian President Dilma Rousseff took the third slot.
First lady Michelle Obama ranked eighth. She was ranked No. 1 last year.
The Associated Press contributed to this report.