Hoeness was sentenced to three years and six months jail in March for evading €28.5million in taxes to the German state and was reportedly taken to Landsberg am Lech prison on Monday.
While Munich's state prosecutor Ken Heidenreich refused to confirm Hoeness has begun his stint in prison, various German media organisations ran the story, while TheLocal.de claimed the former Germany international's legal representatives had confirmed the 62-year-old was in jail.
"We will not make any public statement on that," Heidenreich told Deutsche Welle.
"It's not something we would make public anyhow and there will not be any press release at any point. Mr Hoeness himself would be the person who could confirm that."
Hoeness resigned as Bayern's president when sentenced to jail, ending his 44-year official association with the Bundesliga club.
The former striker played 239 games for Bayern in the 1970s, scoring 86 goals, while he represented Germany 35 times, hitting the back of the net five times.
After he retired, Hoeness immediately became Bayern's general manager, eventually moving up to become president.
