Singing sensation Susan Boyle believes she has put her money to waste and has nothing left for house furnishings, her brother says.

The Scottish singer, who came to international public attention with her appearance on Britain's Got Talent last year, has received $17.3 million in royalties for the sales of her album I Dreamed a Dream, which sold more than 8.5 million copies.

However, she can only purchase clothes from a supermarket, travel by bus, does not own a credit card and cannot pay for furnishings for her new home.

According to her brother Gerry, a management team oversees Boyle's multi-million fortune and gives her $520 a week.

Mr Boyle said his sister has "no concept" of her wealth, is "extremely upset" and is anxious that her savings have vanished.

"When Susan realised she can't just walk into a bank and take out her own money she had a fit because she thought she was down to her last few quid (pounds)," he told Britain's News of the World.

"Her millions are ring-fenced but Susan has no concept of money. She was extremely distressed. She lives in fear of losing everything and returning to her old life before she made it big.

"Susan said to me, 'I've been told I get 300 pounds a week because I'm a novice. I don't have the money to go and buy the furniture'."

He adds that his sister is baffled about money.

"All she wants to do is sing.

"Susan isn't financially astute but she is worried about her situation... And she's got this paranoia that she's going to go back to square one, back to where she was before Britain's Got Talent."

Last month, the spinster spent $61,000 for the semi-detached council home in the Scottish village in West Lothian where she was brought up.

It is said to be her most expensive purchase since she gained fame.