The 48-year-old church volunteer won the hearts of viewers when she confessed to never being kissed, but insisted to Winfrey that she did not feel lonely and was thrilled to be the centre of attention.
The Oprah Winfrey Show sent a film crew over to Ms Boyle's home in Blackburn, Scotland after Britain's Got Talent bosses banned her from flying to the US so it did not look like she was getting better treatment than other contestants.
During the satellite interview, which will be broadcast on Monday, Boyle reportedly predicted that she would not win the contest because of the strength of her rivals, and joked that her cat Pebbles would eclipse her fame after being filmed by the cameras.
Asked by Winfrey whether she was lonely, The Daily Star claims Boyle replied: "Oh no. I am not lonely. Everyone has been so nice. I've got millions of new friends now."
Boyle's appearance on the special episode of Oprah, called The World's Got Talent, is expected to be watched by up to 10 million people.
The special show will feature acts from some of the 40 countries where the show is filmed, including last years Britain's Got Talent contestants, Signature.
Cowell is also expected to be interviewed by Oprah, according to The Daily Mirror.
Boyle has been watched by millions of internet viewers since she first stunned judges with her rendition of I Dreamed A Dream from the musical Les Misèrables.
It has turned her into a global phenomenon with celebrity fans including the actress Demi Moore.
She has already appeared on several US TV programmes including Larry King Live, the veteran interviewer's CNN show.
Boyle remains favourite to win Britain's Got Talent but faces competition from fellow singer Jamie Pugh, the Welsh pizza delivery man who overcame stage fright to sing a tune from Les Misèrables. However, his chances were dealt a blow when it was disclosed that he had sung in a West End theatre before, contradicting his claim that he had never performed before a large crowd.