Merchant Royal, also known as Royal Merchant, was a 17th-century English merchant ship that was lost at sea off Land's End in rough weather on 23 September 1641.

On board were at least 100,000 pounds of gold (over US$1.5 billion in today's money), 400 bars of Mexican silver (another 1 million) and nearly 500,000 pieces of eight and other coins, making it one of the most valuable wrecks of all time.The Merchant Royal spent two years trading with Spanish colonies in the West Indies from 1637 to 1640. England was at peace with Spain at this time. The Merchant Royal and her sister-ship, the Dover Merchant, called into Cadiz on their way home to London. By all accounts she was leaking badly after her long voyage.

When a Spanish ship in Cadiz at the same time caught fire just before she was due to carry treasure to convert into pay for Spain's 30,000 soldiers in Flanders, the Merchant Royal's Captain Limbrey saw his chance to make a little more cash for his owners. He volunteered to carry the treasure to Antwerp on his way home.

The Merchant Royal kept leaking after she and her sister-ship left Cadiz and, when the pumps broke down, she sank off Land's End in rough weather on 23 September 1641.

Eighteen men drowned in the sinking. Captain Limbrey and 40 of his crew got away in boats and were picked up by Dover Merchant. It is not likely that the treasure was taken aboard the Dover Merchant.

Sept. 30, Lond[on].

I suppose you have understood of the loss of the Royal Merchant coming into our road, which is the greatest that was ever sustained in one ship, being worth 400,000l. at least. The merchants of Antwerp will be the greatest losers, for she had in her belonging to them 300,000l. in bullion; if so be the Infante Cardinal lose not upon it Flanders for want of money to pay the soldiers.

– 'Charles I – volume 484: September 1641', Calendar of State Papers Domestic: Charles I, 1641–3 (1887), pp. 114–129