"The worldwide financial breakdown has, as we know, demonstrated the fragility of the present economic system and the institutions linked to it," the pope told the Pontifical Academy of Social Sciences.
The crisis "has also shown the error of the assumption that the market is capable of regulating itself, apart from public intervention and the support of internalised moral standards," he said.
The market "overlooks the essentially ethical nature of economics as an activity of and for human beings," the pope said.
The pope made the remarks as debt-stricken Greece was teetering on the brink of a financial meltdown.
Frenzied negotiations were under way in Brussels between the EU executive, the International Monetary Fund, the European Central Bank and the Greek government over tens of billions of euros in rescue funds.
Worries over the potential impact of the Greek financial crisis on other debt-ridden eurozone nations shook European stock markets early this week.
SIC: FT