She is charged with negligence over the award to Mr Tapie of €404m ($445m; £339m) in 2008 when she was France's economy minister.
Ms Lagarde had appealed against a lower court ruling from December.
She is now expected to appear before a special court for government ministers.
The case stems from Mr Tapie's sale of his majority stake in the sports equipment company, Adidas, which was handled by the state-owned bank, Credit Lyonnais.
The businessman sued for compensation after claiming he was defrauded by the bank and received too little from the sale in 1993.
Read the full article here.