The California grand jury indicted Jackson, the singer's entourage said late on Wednesday.
No official announcement of charges was immediately made, and lawyers for Jackson, subject to a gag order, said they were unable to give details.
The charges would set the stage for a trial in the international spotlight on allegations that Jackson, 45, sexually abused a 12-year-old cancer victim at his Neverland Ranch last year.
The singer has said the accusations are "a big lie" intended to extort money from him.
Following the reports of a grand jury decision, Jackson's lawyers Mark Geragos and Benjamin Brafman said in a statement: "If the grand jury issues an indictment, on Friday, 30 April, 2004 Mr Michael Jackson will appear in court in Santa Maria, California at which time he will enter a plea of not guilty to the charges."
Jackson and his attorneys "are confident that after a trial on these charges, Mr Jackson will be fully exonerated and that the allegations contained in the indictment will be shown to be patently false," the statement read.
The grand jury charges would supersede seven counts laid against Jackson in December by Santa Barbara county prosecutors of lewd and lascivious behaviour with a minor.
There are also two counts of plying a child with alcohol.
Jackson could face a long prison term if found guilty.
Jackson, who was formally arrested in November after raids on his ranch, is now on $3 million dollars bail and he has surrendered his passport.