Scottish Government statistics show a 1.9% increase in emissions in 2010 on the previous year, which has been blamed on the extreme winter weather.
The figure means the statutory target set out under the Climate Change (Scotland) Act to reduce emissions year-on-year has not been achieved.
The Government said the long-term trend still showed a reduction in emissions, down 24.3% since 1990, while provisional figures from the UK Department for Energy and Climate Change indicate that emissions fell 7% in 2011.
Environment minister Stewart Stevenson said: "The Scottish Government remains fully committed to delivering ambitious and world-leading climate change targets.
"We always knew it would be a challenging path to follow when these were set and that year-to-year fluctuations were inevitable.
"It is therefore no surprise that domestic heating emissions rose as a result of the extreme weather.
"Scotland faced its coldest winter temperatures in almost a century - and quite rightly people across Scotland needed to heat their homes to keep warm and safe.
"The longer-term trend reveals Scottish greenhouse gas emissions have fallen by around a quarter since 1990, signalling we are still on track to achieve the 2020 target.
"While the 2010 weather was exceptional, this early experience highlights the need to not just plan to meet the targets, but to build in some contingency as well.
"We remain fully committed to delivering our climate change targets and I am confident that the underlying trend remains downward."
Campaign group Stop Climate Chaos Scotland said the figures underlined the need for action on climate change to be prioritised.
Mike Robinson, a board member of the group, said: "These figures underline the need for greater leadership in actually delivering reductions. World-leading climate legislation needs world-leading climate action.
"It is unacceptable to the thousands of people across Scotland who called for a strong Climate Change Act in 2009 that we have fallen short of this first test.
"Instead of driving the change people called for, the Government has allowed emissions to rise and failed to lock in the drop in emissions caused by the economic downturn.
"We urge the Government to prioritise action on climate change and make low carbon activities central to the forthcoming budget."
Green MSP Patrick Harvie said: "The Government can't get away with expressing shock that Scotland has cold winters some years; this failure of Government policy can't be pinned on bad weather when they have delayed year after year the national, street-by-street effort we need to insulate Scotland's leaky homes.
"Cutting energy bills and carbon emissions at the same time should be a no-brainer.
"Today's figures highlight our damaging reliance on coal and the need for a plan to phase out fossil fuel use alongside the growth in renewables.
"We need a clear timetable set for taking fossil fuels out of the system but the SNP are still intent on extracting every last bit they can find."