Dunga, who captained Brazil when they won the World Cup in 1994, reportedly invested in QPR when the west London outfit was under previous ownership and he is now trying to recover a loan made during that period.
The 47-year-old has hired lawyers Collyer Bristow to pursue his claim in the High Court if necessary, and hopes the current owners of the club, who include Formula One supremo Bernie Ecclestone, agree to repay his loan.
"I loaned my money to QPR in good faith when they needed it and am very disappointed that the new owners, who are very wealthy, are now refusing to pay it back," Dunga said.
"I am fully confident in the English system of justice and that the court will help me recover my loans."
Steven Heffer, of Collyer Bristow, added: "I can confirm I have been instructed by Carlos Dunga to issue proceedings in the High Court to recover the money he lent to QPR.
"I am waiting to hear back from QPR's lawyers whether the loan will be repaid without the need for a court action. It would be inappropriate to say anything further at this stage."