Baker has linked up with Dean Ryan’s men with immediate effect after his recent spell at Stade Montois in France came to an end.
The 28-year-old has three caps for Wales to his name and has signed with the Dragons until the end of the season.
Ryan, Director of Dragons Rugby, said: “We’re pleased to bring Dan back to Wales and into our environment.
“He is eager to take the opportunity and we look forward to seeing the impact he can make for us in the second half of this season.”
Back-row forward Baker represented Swansea before making his regional debut for Ospreys in 2013 where he would go on to make 94 appearances.
He was first selected by Wales in May 2013 for that year’s summer tour to Japan. He made his international debut against the Cherry Blossoms in June of that year.
Baker played both Tests against Japan in 2013 and also featured against Ireland in a warm-up for the 2015 Rugby World Cup.
“I’m excited to be returning to Wales and the chance to represent the Dragons,” Baker said.
“I enjoyed my rugby experience over in France, but now my focus is getting involved here as soon as possible.
“There is a talented squad at the Dragons and from my conversations with Dean the ambition is very clear.
“I’m excited to play my part and look to show what I can do the rest of this season.”
