The Greek economy, struggling in a fifth year of recession, shrank 6.2 per cent in the second quarter compared with a year earlier, according to official data.
The economy contracted 6.5 per cent in the first quarter, worse than the initially given 6.2 per cent, according to revised figures issued in June.
The Bank of Greece expects the economy to shrink 4.5 per cent for 2012 as a whole, following a 6.9 per cent drop last year.
Greece is relying on two financial rescue packages backed by the European Union, the International Monetary Fund and the European Central Bank worth about 240 billion euros ($A281.18 billion) for its economic survival.
Last year, private creditors agreed to write off more than 100 billion euros in debt, roughly half the amount they were owed, as part of a second bailout program.
Harsh austerity measures and economic reforms linked to the aid agreements have taken their toll on the economy, with unemployment hitting record highs.
Greece's conservative-led coalition government has yet to finalise spending cuts of about 11.5 billion euros in order to unlock its next aid instalment, worth about 31 billion euros.