Originally from Brecon, the forward has signed a one year deal with the men of Gwent.
The talented back row is a vastly experienced player, who has represented Wales and was also a member of the British and Irish Lions squad in 2009.
The 32-year-old has played for Wigan Warriors, London Wasps, Cardiff Blues and has also had spells with Newport RFC and Llanelli Scarlets.
On signing for Newport Gwent Dragons, Powell said, "I am extremely delighted to be back in Wales. I have very fond memories of playing for Newport RFC and can remember the great support we had from fans when I previously played for them.
"I have been very impressed through the season with both Kingsley and Lyn's ambitions for the region. I am very excited for the challenges that lie ahead and look forward to challenging the other Welsh regions for silverware."
Dragons head coach Kingsley Jones, added, "I am very excited that we are bringing Andy back to Gwent to play.
"He has the X-Factor and brings a lot to the team dynamics not forgetting his great ball carrying skills.
"He will be coming back here to challenge the likes of Taulupe Faletau for a first team spot as well as adding experience to the squad."
To watch Andy play next season alongside the likes of Aled Brew, Lee Bryne and Taulupe Faletau then purchase your Early Bird Season Ticket now, from as little as £99 for adults or £10 for Under 16s. Call the Ticket Office on 01633 674990, to book yours now.
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