The talented number nine, who played in his country’s famous win over New Zealand last November, has made the move to Wales and joins Dean Ryan’s men with immediate effect.
The 26-times capped international star also appeared for the Pumas at the 2019 Rugby World Cup and joins on a deal until the end of the season.
Bertranou, 27, last featured for Jaguares in Super Rugby.
Ryan, Director of Dragons Rugby, said: “We’re pleased Gonzalo joins us and excited to see the impact he can make at the region.
“Gonzalo brings quality into our set-up and his international experiences will help the wider squad to grow.”
Bertranou said: “I’m looking forward to starting to train and play with the team. I’m very happy.
“This is my first time in Wales, so it is an exciting time for me. It is a good opportunity for me to prove myself.
“I love the way the Wales team plays and obviously Dragons too, so I am now looking forward to start playing.”
Dragons have also confirmed full-back Ioan Davies has joined the region on loan from Cardiff Blues until the end of the current season.
