Scotland's public bodies have received more than 400 requests for information since new rules on openness came into force at the start of the year.
Mr Dunion is encouraging people to use the new law
Information Commissioner Kevin Dunion revealed the figure as he prepared to launch a public awareness campaign about the Freedom of Information Act.
Mr Dunion said research has shown that only about 30% of people in Scotland have heard of the act.
The Right to Know campaign would seek to address the shortfall, he said.
Speaking on BBC Radio Scotland's Sunday Live programme, Mr Dunion said: "The purpose of the legislation is to allow anybody, anywhere to ask Scotland's public authorities for information.
"We know from research that we've carried out that only about 30% of people have definitely heard of the act and even then they're not entirely sure of what they can do in terms of using those rights.
"The whole purpose of the Right to Know campaign is to explain, in plain English, what the Freedom of Information Act is all about, what kind of information you can get and from which authorities."
The act applies to the Scottish Executive and its agencies, local authorities, NHS Scotland, schools, colleges and universities, the police and the Scottish Parliament. Other bodies can be added to the list in the future.
Mr Dunion said individuals can apply for any information from public authorities and it would then be up to those bodies to provide it or provide a clear and justifiable case for refusing to do so.
It is his job to enforce the public's rights and adjudicate in contentious cases.
The commissioner said the publicity campaign was geared towards increasing public confidence in the new system and encouraging people to seek information on the "bread and butter issues" that affect their lives.
The new law came into effect on 1 January this year
He rejected a calls for the act to be suspended during election campaigning to stop dirty tricks campaigns by parties.
Former Prime Minister John Major called for a moratorium around election time after controversy over the release of papers on Black Wednesday in 1992, when Britain crashed out of the Exchange Rate Mechanism.
Mr Dunion said: "There is no going back on this. We can't put the genie back in the bottle. The Freedom of Information Act in Scotland gives people an absolute right to information held by Scotland's public authorities.
"We can't on a weekly or monthly basis decide whether or not to suspend that right.
"The act applies not just to central government but to local authorities, the police, right down to individual GPs and dentists.
"There is no way they can suspend the act on an arbitrary basis and we should remember of course that the Freedom of Information Scotland is entirely separate from the English act, so his comments have no bearing whatsoever."
The interview was broadcast in full on 13 February during the Sunday Live programme on Radio Scotland.