Terms of the deal, which could be announced as soon as Tuesday, weren't disclosed, according to The Wall Street Journal, citing people familiar with the matter. As of Friday, ADT had a market value of $4.4 billion, suggesting a potential deal value greater than $5 billion.
The purchase would be one of the largest leveraged buyouts in recent years, according to the report, a sign of strength in the dealmaking arena despite tumultuous markets this year.
Representatives of Apollo Global couldn't immediately be reached for comment.
Shares of ADT, indicated higher in after-hours action, closed Friday at 26.87, up 1.9%. Shares are off more than 31% over the last 12 months.