It was a flawless opening round from the world number two McIlroy, who began on the back nine and hit four birdies in the first nine holes and followed up with five birdies to lay down an early marker.
"I didn't expect that, it didn't feel quite as good as that the first couple of days when I was here hitting balls and playing the course," McIlroy said.
"I surprised myself a little bit but hopefully more of the same over the next few days."
Germany's Paul kept pace with McIlroy over the first nine holes, despite hitting a bogey at the fifth, but with McIlroy scoring two birdies on the final three holes, Paul parred all three to finish on seven-under.
South Africa's Thriston Lawrence is three shots off the lead with England's Tommy Fleetwood and Thorbjorn Olesen of Denmark a further shot back on five-under.
The inaugural Dubai Invitational is the opening event of the 2024 DP World Tour and has a total prize fund of $2.5 million dollars.
