"It's an exciting time for the Blues moving into the new stadium and also the superb new training facilities have been great."
Roberts, 22, has played 47 times for the Blues, and was instrumental in the the 2008/09 season when they reached the semi finals of the Heineken Cup and lifted the EDF Energy Cup at Twickenham.
A series of fine performances for the region saw him called up to the 2009 Lions tour of South Africa where he formed a formidable partnership with Brian O'Driscoll where he was named Lions Players of the Series.
"I'm fortunate that I've tasted some success early in my career but I remain as focused as ever to play my part in a successful Cardiff Blues team," he said.
The Blues have also confirmed John Yapp will be with the region for a further three years, despite his recent struggles with injury.
Yapp tore his bicep during the Blues' victory over the Harlequins in the Heineken Cup. He is expected to be back in action for the Blues early in early Spring.
Cardiff Blues Director of rugby David Young said: "Both John and Jamie are integral to our plans going forward with the Cardiff Blues, so I'm delighted that they have both signed new contracts with the region."
"They are both local boys who have come through the system and it shows our commitment to developing and keeping local talent."
"Both players have achieved a lot in their careers so far but I'm sure we haven't seen the best of John and Jamie yet."
"We are building a strong squad here at the Blues and to keep the services of quality players is hugely important to us."