Joe Jackson says that Michael is making a bigger impact than ever since his June death from an apparent drug overdose.
"He's worth more dead than when he was alive," Joe, 80, tells "Extra" in an interview that airs Thursday night. "I'd rather have him alive."
As Michael's movie "This Is It" rakes in $2.2 million in the box office, Joe adds, "When he was living, they didn't show this."
See 30 photos from the "This Is It" premiere
Joe admits he wasn't on board with the flick at first, which documents Michael rehearsing for his comeback tour of the same name.
"I didn't know what 'This Is It' meant," says Joe, who spoke to "Extra" in Las Vegas at the unveiling of a celebrity star honoring him and his famous family.
But the movie allows him to remember Michael "as I knew him best: performing and dancing on stage. Entertaining people," he says.
Hearing Michael's songs make Joe "very emotional," he admits. He sometimes sheds tears "when I'm off to myself and I start thinking about things that we went through," he says. "No one will ever see me, though."
He has harsher feelings for his son's doctor, Conrad Murray, who is currently under investigation on manslaughter charges.
Joe says if he saw Murray, he'd "knock him out."
For more of "Extra's" exclusive interview with Joe Jackson, tune into Extra Thursday night!