The celebrity gossip title claims the photo is the last one showing Jackson alive after his fatal heart attack.
A source told Media Week in the US that Northern & Shell, OK!'s publisher, paid roughly $500,000 for the rights to the photo in the US and the UK.
The photo looks almost identical to one posted on 'Entertainment Tonight's' website ETonline.com.
Hello magazine, OK!'s rival, is also running a Michael Jackson tribute issue this week, but its cover image is of the star waving goodbye in a shot taken a few years back.
Sarah Ivens, editorial director at OK!, told MediaWeek.com that she thought the dying Jackson photo would differentiate OK! from the other magazines running tribute issues this week.
Ivens said: "It's a photo that captures the surprise and the upset and the moment of this breaking news story.
"I hope the cover will provoke readers. It celebrated the man, but it also does expose that he was an eccentric character who lived a very controversial life."
Natmags is releasing a one-off commemorative Michael Jackson tribute magazine today.
The 132-page title is entitled 'Michael Jackson - Tribute to a Legend'. A total of 200,000 copies of the glossy A4 title will be on sale for a month, priced at £2.99.
Separately, the latest edition of monthly music magazine Q also features Jackson as the cover star, but the issue was printed and distributed before the singer's death and was produced to coincide with his 02 concerts.
Paul Rees, Q's editor, said in a statement: "Michael Jackson's record-breaking residency at London's O2 Arena was always destined to be the year's biggest music story, one way or another.
"As such, three months ago we decided to put Jackson on the cover of the issue of Q that will go on sale tomorrow and throughout the month of July, when the first batch of dates were due to take place.
"Work on this issue was completed a fortnight ago and it was printed shortly thereafter. When news of Michael Jackson's death broke in the early hours of Friday morning, it was already being distributed.
"As such, we have had no opportunity to change any of the editorial content within the issue. Such is the risk inherent in producing a monthly magazine -- that events may overtake a story that you are committed to.
"If you do take offence to any part of the issue in light of Michael Jackson's tragic passing, I can only apologise on behalf of Q.
"Hopefully, you will understand that no offence was intended or meant."