Tymoshenko, a former prime minister, was sentenced in October to seven years in prison following a conviction on charges she abused her authority when she helped broker a 2009 natural gas deal with Russia's Gazprom.
The deal broke a gas impasse, though Kiev's government claims the terms bruised an already weakened economy.
Ukrainian Deputy Prosecutor General Yevhen Blazhivskiy said Tymoshenko faces a $2.4 million suit on charges she mismanaged funds while serving as head of United Energy Systems in the 1990s, Russia's state-run news agency RIA Novosti reports.
Tymoshenko earned the nickname "gas princess" during the 1990s on allegations she may have sold stolen natural gas through United Energy Systems, the primary importer of Russian gas.
Tymoshenko denies the charges. Her supporters say the allegations are politically motivated.
The prosecutor said the case could go to court next week.