"We are excited that KG has decided to continue his career with us," said Timberwolves president and coach Flip Saunders. "When we acquired him last year we hoped this would evolve into a longer term relationship."
The two-year deal is reported to be worth $16 million.
Garnett played just five games with the Timberwolves last season after the team re-acquired him in February. The 20-year NBA veteran was battling injuries, but he seems ready to go for next season.
"I'm excited to be part of this process for the future," Garnett said in a statement through the team. "I can't wait to build something special with this group of guys. Hopefully I can help, teach, and also continue to grow and learn from the young guys. It should be great... I'm looking forward to it all. The process to greatness starts now!"
Garnett returned to the Wolves after spending most of last season with the Brooklyn Nets. Between the two teams, he played a total of 47 games, averaging 6.9 points and 6.6 rebounds.
Some of the young Wolves begin play in the Las Vegas Summer League Friday night. The Star Tribune reports Garnett is expected to spend some time with those guys.
Originally drafted by the Wolves with the 5th pick in the 1995 NBA Draft Garnett played his first 12 seasons with the Wolves, before he was traded to Boston in 2007.
If he fulfills his new contract, KG will join Robert Parish and Kevin Willis as the only three players to have played in the NBA for 21 years.