The ex-Manchester City forward has signed a four-year deal to keep him in charge until 2028.
As a player, Bellamy featured in over 400 Premier League matches and represented the Welsh national team 78 times - captaining the country between 2007 and 2010.
He had been a part of Burnley's coaching set-up after calling time on his playing career and also had stints working behind the scenes at Cardiff's academy and Wales' under-21 squad.
"It's an incredible honour for me to be given the opportunity to lead my country and it's the proudest moment of my career," Bellamy said.
"It was always my ultimate dream to become the Cymru Head Coach and I am ready for the challenge.
"I will give my full commitment to develop this team and I am passionate to bring continued success into Welsh football."
His first game in charge will be against Turkey on September 6th in the UEFA Nations League.