The 61-year-old former West Germany international has confirmed the enquiry is related to the January disclosure of a bank account in Switzerland
The former West Germany international declined to discuss the precise details of his case but did confirm it centres on a Swiss bank account.
"I filed a voluntary disclosure about the account to my accountant at the tax office in January 2013," Hoeness is quoted as saying by German magazine Focus.
"I trust fully in the work of the authorities involved in the case and ask for there to be respectful refrain from further enquiries."
Hoeness is currently looking forward to Bayern's eagerly-awaited Champions League clash with Barcelona on Tuesday night.