It extends BBC Sport's current deal, which runs until 2013, as exclusive broadcaster of the Six Nations and covers TV, radio and online.
This year's tournament saw audiences increase to their highest level for 13 years, with an average audience of 4.7m per match.
"The Six Nations is a crown jewel in the sporting calendar," said BBC director of sport Barbara Slater.
The championship, the premier annual northern hemisphere rugby union tournament, is contested by England, Ireland, Scotland, Wales, France and Italy every February and March.
"We're delighted that we can continue to bring the tournament to our audiences," Slater added.
"Viewing figures continue to grow year on year and we look forward to continuing to work in partnership with the Six Nations to build interest even further through the BBC's unparalleled offering of TV, radio, online and interactive services."
In total over 30m people within Britain watched some of this year's tournament.
Among the most memorable matches in the 2011 edition were Italy securing a first ever Six Nations win over France and England, who had won their first four matches, being denied the Grand Slam when they lost to Ireland.
John Feehan, chief executive of the Six Nations, added: "We are delighted that BBC Sport will maintain, extend and enhance its coverage of the RBS Six Nations, the world's biggest annual rugby tournament, for a further four years to March 2017."
The BBC has agreed a deal to broadcast the Six Nations until 2017.