The 40-year-old is currently asymptomatic and self-isolating in Belo Horizonte in Brazil.
"I've been here in BH since yesterday, I came to participate in an event," Ronaldinho said on Sunday.
"I took the test and tested positive for COVID. I'm fine, asymptomatic, but we'll have to leave the event for later. Soon we will be there together. Big hug!"
Ronaldinho’s positive diagnosis caps a turbulent year for the two-time FIFA Footballer of the year, who spent five months in detention earlier this year in Paraguay for a fake passport issue.
Ronaldinho was arrested in Paraguay on March 6 with his brother Roberto Assis for entering the South American country without the right documentation.
The pair were in the country to partake in a number of promotional events.
After initially spending 32 days in the Agrupacion Especializada prison, they were released on April 7 and placed under house arrest at the Hotel Palma Roga in Asuncion until investigation into the case was concluded in August.
Ronaldinho is widely considered as one of the greatest footballers of all-time, having won the FIFA World Cup with Brazil in 2002.
He won two La Liga titles and the UEFA Champions League during his time with Barcelona and also turned out for the likes of AC Milan and Paris Saint Germain in an illustrious career before retiring in 2015.
