The Scottish Crime and Justice Survey found that just 37 per cent of crimes were reported to Police Scotland in 2016-17.
The survey, based on interviews with almost 5,600 adults, also revealed that 39 per cent of people thought appropriate punishments were given to offenders.
Less than half (47 per cent) were confident about the efficiency of the justice system, but 78 per cent were sure that it allows for a fair trial.
The research revealed that adults experienced 712,000 crimes over the period, down 32 per cent from 2008-9, but unchanged since 2014-15.
More than two-thirds (68 per cent) of this was property crime such as vandalism or theft, with the remainder being violent crime such as assault or robbery. Violent crime was also down 27 per cent since 2008-9.
The figures suggested that there had been an increase of 45,000 violent crimes when 2016-17 was compared with 2014-15. But the authors of the Scottish Government study said the increase was not statistically significant.
When asked why crimes were unreported, the reasons given included the matter being dealt with by those involved, it was reported to other authorities or it was regarded as a private matter.
Although a majority (58 per cent) said the police were doing a good or excellent job in the community, the figure was down from 61 per cent in 2012-13. Those living in poor areas were less likely to have confidence in the justice system and believe police were doing a good job.
Scottish Conservative justice spokesman Liam Kerr said: “This survey repeatedly highlights how out of touch the SNP justice strategy is and, as a result, public confidence in the police is diminishing.
“The SNP soft touch approach to crime abandons victims, undermines the police and enables criminals to walk away from punishment.”
Justice Secretary Michael Matheson said: “Scotland’s firm focus on prevention, responsive policing and local partnerships to help individuals and communities keep themselves safe has had a positive impact on long-term crime trends and people’s feeling of safety, with recorded crime at a 43-year low. While this progress is cause for encouragement, it will never be an excuse for complacency.”
He added that further research had been commissioned into violent areas.