He hasn't proposed to Niall Horan, although they would make a lovely couple, he has of course allegedly popped the question to his girlfriend of almost a year, Erica Stoll.
So, why does the internet think the 26-year-old no. 1 golfer has proposed? He posted a picture of the Eiffel Tower to his Facebook.
When his reps were approached regarding the alleged proposal, one reportedly said: "We don’t comment on speculation about our client’s personal life." A source speaking via the Independent, however, claims that "McIlroy has popped the question and the happy couple are over the moon."
Speaking of his Stoll last month, he said: "She is from America which is why I like to spend time in Spring Beach. She doesn't play golf but she is involved. I am very happy in my love life. If everything off the golf course is good, it allows you to be better on it as well."
— GolfPunkHQ (@GolfPunk_Mag) December 3, 2015
The golfer, who is worth in the region of €400m, endured a public breakup with former fiance - tennis ace Caroline Wozniacki - in May 2014, not long before their wedding was due to take place in New York. Speaking at the time, Rory said: "The wedding invitations issued at the weekend made me realise that I wasn’t ready for all that marriage entails."
Neither Stoll nor McIlroy have confirmed or denied the engagement rumours.