The Scottish Retail Consortium (SRC) said total sales growth had been negative in seven out of the last 12 months north of the Border.
It compares with just one negative month in the past year in the rest of the UK.
Overall, data published by the British Retail Consortium (BRC) shows UK retail sales growth is now averaging half what it was in the years before the Lehman Brothers collapse.
The report said the data showed the impact of the global financial crisis on UK retailers was "severe and long-lasting" and comes amidst concerns the closure of shops is creating waves of "ghost towns."
The average level of vacant stores in London is 13%, but Scotland's is nearly 17%.
Retail sales in the UK took another hit last month as people put off shopping to watch the London Olympics.
SRC spokesman Richard Dodd said it was clear Scottish retailers had been having a tougher time than the rest of the UK.
"There was a long period, which coincided with the run-up to the banking crisis, where Scotland was outperforming the rest of the UK, but that is no longer the case," he said.
"A lot of that is down to the proportion of the economy that relies on the public sector and the impact of public spending cuts, including the pay freeze. It is important for the Scottish Government to appreciate that consumer confidence needs to be boosted by not adding extra costs to households and not adding extra costs to business through regulatory burdens."
However, David Pierotti, centre director for the Silverburn shopping centre on the outskirts of Glasgow, said there were positive signs.
"It is challenging and we are down 2% in the number of customers coming into the centre compared to last year.
"However, there are lots of contradictions, with strong performance in restaurants and coffee, where sales have been very buoyant."
The BRC data was published to coincide with the fourth anniversary of the Lehman Brothers banking failure.
The consortium called on the Westminster Government to restore consumer confidence by controlling costs – for example by scrapping the postponed fuel-duty increase now due in January, and by freezing business rates in 2013 after two years of rises.
The report found year-on-year growth in the total value of retail sales has averaged just 2.1% over the last two years. That is below inflation, meaning sales volumes have stagnated. It compares with much stronger growth of 4.5% over an equivalent period before the crisis.
Like-for-like sales value growth has hovered around zero over the last two years.
Meanwhile, a separate survey found the public was more positive about personal finances than in the previous two-and-a-half years, although the outlook was still gloomy.
Some 40% of households predict their finances will deteriorate over the next 12 months, the lowest figure since March 2010, while some 30% expect to see an improvement
The Markit household finance index study found people working in IT and telecoms tended to be the most positive, while those working in health, education and social care tended to be the most downbeat.