The 32-year-old back-rower has been hindered by niggling injuries this season, and he is set to miss the entire tournament after picking up a hamstring problem in the Ospreys Heineken Cup defeat against Leinster on Friday.
His Ospreys colleague James King, who can play in the back row and at lock, has been called up as his replacement.
A Welsh Rugby Union statement read: "Wales have released Ospreys back-row Ryan Jones back to his region due to injury.
"Jones met up with the squad this morning as they began preparations for the forthcoming RBS 6 Nations and has been ruled out with a hamstring injury.
"Jones' regional team-mate James King, who made his debut for Wales last summer in Japan, has been called into the squad."
Jones had played a part in Wales' Championship triumphs of 2005, 2008, 2012 and 2013. He has won 75 caps for his country and captained them to Grand Slam success in 2008,
The loss of a player of Jones' experience adds to Wales head coach Warren Gatland's concerns, with Ian Evans facing a possible ban.
The Ospreys lock was sent off for alleged stamping against Leinster and will face a disciplinary hearing.
Captain Sam Warburton has not played since the autumn defeat to Australia due to a shoulder problem, although he is expected to be fit for the tournament opener against Italy, while prop Gethin Jenkins is recovering from a leg injury.
Hooker Richard Hibbard is also nursing an injury after hurting his hip during the Ospreys' loss in Dublin.
Centre Jonathan Davies is making good progress in recovering from a pectoral injury but still looks set to miss the opening two games against Italy and Ireland as Wales look to become the first side to win three outright titles in a row.
In addition to the call-up for King, who can play in the second row as well as the back row, two players will train with the squad from Tuesday in the form of Newport Gwent Dragons hooker Sam Parry and Scarlets second-row Jake Ball.