Wales fly-half Jones has been out of action since New Year's Eve, while his international colleague has been sidelined since November.
Jones picked up a minor shoulder injury in the Magners League win at the Dragons and hooker Rees suffered a groin tear in his country's autumn defeat to Australia.
But both players have been named in the Scarlets squad to face Brive in the European Cup this Saturday as the region look to build on last week's stunning victory over London Irish that kept their quarter-final qualification hopes alive.
The Scarlets travel to France on the back of a superb comeback win over one of England's leading sides and head coach Nigel Davies admits that the return of his star pair will only add to the growing confidence within the camp.
"It is great to have some of our senior guys back. Having experience is very important particularly away from home in Europe," said Davies.
"Having said that, the younger boys who played on Sunday will have gained a lot from that win and comeback. They know now that they can stay in games and by being determined you can come through and win.
"I was very impressed with the way our bench went on Sunday - it's that quality we need to impact games and all three of the forwards who came on made an impact.
"Damian Welch has been working hard, he's a great athlete and can be very quick and as a line-out forward he was very effective last weekend."
Rees, who had originally been expected to be absent for up to three months, admits that he is delighted to be returning to a squad who have shown what they can achieve when belief is coupled with application.
"The result last weekend proves what we can do as a squad and puts us in good stead for this weekend," added Rees, who is named among the replacements for the final group game.
"But we know its going to be tough, a physical challenge out there. Brive have got some good players, so it's been important that we've prepared well and chuck everything at them and the boys are really up for the challenge.
"We are moving forward in the right direction now and there are a lot of young players here who have had a lot of game time this season and are coming through really well.
"A quarter-final place in either the Heineken or Amlin Challenge Cup will inspire our youngsters and I think we would all be proud of having achieved that."
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