The latest Export Statistics Scotland report shows Scotland sold goods and services worth 49.8 billion to the rest of the UK in 2015.
Exports to the EU amounted to 12.3 billion in the same year.
Scotlands trade with the rest of the UK and exports to the EU grew at the same rate 4.4 per cent - between 2014 and 2015.
The figures are revealed in the latest Export Statistics Scotland report, a National Statistics publication published by the Scottish Government.
David Mundell, the Secretary of State for Scotland said:
Our own domestic market in the UK is far and away the most important market for Scotlands businesses. The Scottish Governments own figures show our trade with the rest of the UK is worth four times our exports to the EU.
Businesses in Scotland sold 37.5 billion more in goods and services to their own market in the UK than they did to all 27 EU countries put together.
Todays figures show the UK is the vital Union for Scotland, and highlight the importance of maintaining the UK market and preventing any new barriers to doing business across the UK as we leave the EU.
We know the Scottish Governments constant talk of a second independence referendum is creating damaging uncertainty for the Scottish economy. I again call on the First Minister to end that uncertainty by taking her threat of another referendum off the table and working with us to get the best deal for Scotland and the whole of the UK.