Speaking during a traditional Ash Wednesday address in northeastern Germany, Merkel said: "It is a scandal if it turns out that the banks who led us to the brink were also complicit in falsifying statistics in Greece."
According to media reports, Wall Street banks found ways of allowing Greece to hide its mounting debt, enabling the country to evade European Union censure.
One deal created by Goldman Sachs helped obscure billions in debt from budget overseers in Brussels, a report in the New York Times said earlier this month.
Merkel also further ramped up the already considerable pressure on Greece to take drastic measures to bring down its budget deficit, which is more than four times the maximum allow by the EU treaties.
"Just like in Germany, which is running a very sensible budgetary policy, we except other countries in the euro area - I am talking especially about Greece - to follow such a policy," she said.
She said she agreed with Greek Prime Minister George Papandreou that "Greece must now take hard savings measures."
Nevertheless, she defended the euro, the common currency shared by 16 European member states that has come under immense pressure during the Greek crisis.
"If we had not had this common currency during the economic and banking crises we have suffered in the past few years, we would have experienced completely different turbulences," she said.