The Ghanaian striker suffered a stroke back in 2015 which left him debilitated just two years after retiring from playing.
According to a number of reports in Ghana, he passed away in London on Thursday morning at the age of 40.
Agogo was a star of the national team and the poster boy of the 2008 African Cup of Nations hosted in Ghana.
He scored 12 goals goals in 27 caps during the height of his career between 2006 and 2009.
Agogo enjoyed the best spell of his career with Nottingham Forest between 2006 and 2008, scoring over 20 goals for the club.
He opened up on his health problems in an emotional BBC interview called “Speechless” two years ago, discussing his battle to regain his speech.
“I was running with my dog. I was coming back home. I was near the Marriott Hotel and the stroke happened,” he said.
“When I woke up I was in hospital with my mum. I couldn’t speak. I was in a bad way.
“I had thoughts, but I was like where is my voice. I was baffled, man.”
Agogo started his career with Sheffield Wednesday during their time in the Premier League, making two appearances for the club, before a stint in the United States.
He returned to England with QPR in 2002 then moved to Barnet, bagging 19 goals in 39 games to earn a move to Bristol Rovers.
It was with Rovers that he starred with over 40 goals across three seasons, earning his move to Forest and firing them into the Championship.
He scored 13 goals as they earned promotion to the Championship from League One before being sold to Zamalek in 2008.
He finished his career in Scotland, being signed by former Forest boss Colin Calderwood at Hibernian on a one-year deal in July 2011.
Agogo scored once in 14 appearances before retiring at the end of the season.
On the international stage, he scored the winner for Ghana in the 2008 African Cup of Nations quarter-final against Nigeria and was a key part in their third-placed finish.