Majorities in most countries - on average 68 percent - also see the need for major changes to their own country's economy.
Of the 24 countries polled, 15 are part of the G20 and among those countries, 65 percent think major changes are required to the international economic system, while 62 percent see the need for major changes to their own country's economy.
When asked whether the downturn in the global economy has negatively affected them and their family, over six in ten (62%) said it had affected them at least "a fair amount".
More than two in five (44%) say they have been personally affected by shortage of credit for mortgages and other loans at least a fair amount.
The poll also shows that despite recent price falls, the high cost of food continues to negatively affect a much higher proportion of people than the economic downturn. Three in four families (76%) across the 24 countries say it is affecting them at least a fair amount, with 47 percent saying it is affecting them a great deal, down from 59 percent six months ago.
The results are drawn from a survey of 29,913 citizens across 24 countries, conducted for BBC World Service by the international polling firm GlobeScan, with the Program on International Policy Attitudes (PIPA) at the University of Maryland. GlobeScan coordinated fieldwork between November 24, 2008 and February 27, 2009. The margin of error ranges from +/-2.3 to 3.5 percent.
GlobeScan Chairman Doug Miller commented, "The poll reveals a global mandate for bold action at this week's G20 leaders summit. Results suggest most people see the global economic system as flawed."
He added: "The poll also highlights the 'forgotten crisis' of high food prices that is still having the most negative impact on many people's lives."
