In a wake-up call to the rival camps, most voters said they struggled to tell whether politicians' claims were true, and complained the campaigns had not covered issues important to them.
Only 14%, about one in seven, said they were "very well informed" about the issues at stake. The figure fell to just 10% among women voters, the Ipsos Mori survey showed.
The Law Society Of Scotland, which commissioned the poll, called on bodies ranging from business and professional organisations to charities, churches and trade unions - to step in to help fill gaps in people's knowledge.
Bruce Beveridge, the society's president, said: "The importance of the question facing us in September demands a thorough and worthy debate.
"This poll shows many Scots still do not feel properly informed.
"The responsibility to engage people and to ensure the right questions are being asked and answered on both sides of the debate, lies not just with politicians and the official referendum campaigns but also with companies and organisations."
He added: "Civic Scotland, including the Law Society Of Scotland, has to work harder to ensure people feel they can make an informed choice come September."
He said the society planned to publish more information over the coming months to help inform the debate and join forces with other organisations to organise referendum-related events.
Just over 1000 people were questioned at the end of November and early last month, shortly after the Scottish Government launched its independence White Paper.
Forty two per cent said they were "fairly well informed" but 34% said they were not well informed and 9% answered they were not at all informed about the issues.
More than two thirds (67%) said they found it difficult to decide if information being provided in the debate was true or not.
Just four out of 10 people said the debate so far had been helpful in deciding how they would vote in the ballot.
More than half of those polled (53%) said the debate had been interesting "for people like me".
But 54% thought the debate had not so far covered the issues that were important to them.
Better Together, the cross-party pro-UK campaign, backed the Law Society Of Scotland's call for other bodies to become more involved in the debate.
A spokesman said: "The campaigns are working to get information out to people across the country about the impact of going it alone on our jobs, pensions and public services.
"However, we need others to get involved and to speak out.
"The Nationalists only need to win once and by one vote for Scotland to buy a one way ticket to a deeply uncertain destination."
Yes Scotland, the pro-independence organisation, called on the No campaign to explain the consequences of remaining part of the UK.
A spokesman said: "We know that as people become more informed, they tend to move to Yes, so it is a priority for us to make sure people in Scotland are well informed.
"Our website has a wealth of information for those wanting to learn more about the benefits of a Yes vote and the Scottish Government's recent White Paper provides the most detailed blueprint any country has ever had at the point of independence.
"What is missing is an equivalent document from the No campaign, setting out what will happen to the powers of the Scottish Parliament and to the funding of Scottish public services if we vote No in September."