Jackson, who was married to and divorced from Lisa Marie Presley and Debbie Rowe, died June 25 of cardiac arrest after a suspected prescription drug overdose. He was 50.
Although there has been much speculation about Jackson's sexuality throughout his life, the singer always maintained he was heterosexual.
The New York Post quoted investigative journalist Ian Halperin as saying in his book "Unmasked: The Final Years of Michael Jackson" that "virtually everybody I've interviewed about Jackson has told me: He's gay."
"Even those who are his most ardent defenders, people who maintain that he is innocent of the molestation charges, insist that he is homosexually inclined," Halperin wrote in the book due out this week. "In the course of my investigations, I spoke to two of his gay lovers, one a Hollywood waiter, the other an aspiring actor. 'Lawrence' said Jackson was introduced to him by the sister of one of his aides. Their affair was short but 'passionate' and took place almost every night for three weeks at the actor's home in the Hollywood Hills."
Halperin also said Jackson left his upscale residence in Las Vegas in 2007 to meet another boyfriend at a run-down motel.
"He met a construction worker and fell madly in love with him," a source said to have been close to Jackson told Halperin. "Michael would leave the house in disguise, often dressed as a woman, and would go meet his boyfriend at a motel that was one of Vegas' grungiest dives. Michael was broke. He struggled to put food on the table for his children. That was all he could afford then."