Rakhat Aliyev is suspected of complicity in the murder of two former managers of his bank in Kazakhstan in 2007. The report cites "overwhelming evidence".
Aliyev, who remains in custody after voluntarily returning to Austria from Malta to defend the charges, consistently denies the allegations against him.
He describes himself as a victim of politically-motivated prosecution by his former father-in-law, Kazakh President-for-life Nursultan Nazarbayev , with whom he had fallen out of favour.
Evidence emerged in June including Skype calls that undermined his alibi for the murder.
A court in the central Asian republic of Kazakhstan found him guilty of the murder of two bankers who were kidnapped in 2007 and found dead in 2011.
Austria twice refused to extradite him, believing he would not receive a fair trial back home.
In July 2011, Austrian justice launched its own enquiry against Aliev, who had since left for Malta.
OE1's Morning Journal reports that the prosecutor's report, in which two additional co-conspirators were included, should already be with the Justice Department, meaning that formal charges are imminent.