Emerging from a European Commission project, it warns that technology could lessen the trust governments have instilled in citizens before now.
Officials must move beyond security measures to reassure people about how they are being treated, it said.
The report comes as the UK government tries to reassure Britons after losing data records for 25 million people.
The report was written by a research body, bankrolled by the EC's Information and Society Unit, that is looking at "citizen-centric" e-government.
The cc:eGov unit points out that increasingly technology, often in the form of websites, is the means by which citizens encounter local and central government.
Frank Harris, author of the report, wrote: "People learn to trust others through experience, and through judgement based on both direct and referred experience."
The danger, he warned, was that these interfaces did not engender the same feelings of trust that have emerged via more traditional routes.
He added that to engender trust in electronic channels required much more than the basic requirements of security.
Citizens may not recognise the significance of technical measures, such as encryption, which try to stop criminals eavesdropping while they use a government website.
Instead, he said, more obvious means, such as kite marks or privacy seals, may be needed to reassure people.
He called for the establishment of a clear "pact" between citizens and government that says clearly what will be done with information people hand over, and what happens when data is lost or things go wrong.
As evidence of what form this might take, the report cites the Dutch "e-citizen charter", a 10-point code of conduct the government has pledged to abide by.
Without a mechanism for engendering trust, efforts to drive e-government may struggle, wrote Mr Harris.