The 52-year-old businessman has taken to the micro-blogging platform - which was formerly known as Twitter - to confirm that his planned fight with the Facebook co-founder will be streamed on X.
Elon - who bought X for $44 billion in 2022 and recently announced a rebrand of the platform - wrote online: "Zuck v Musk fight will be live-streamed on X."
"All proceeds will go to charity for veterans."
No date for the billionaire boxing brawl has been announced yet.
Elon also revealed that he's busily preparing for the fight.
He said: "Am lifting weights throughout the day, preparing for the fight.
"Don’t have time to work out, so I just bring them to work."
Earlier this year, the tech billionaires announced plans to stage a cage fight.
Elon and Mark, 39, exchanged messages over social media and confirmed that they were both keen on the idea.
Elon joked at the time: "I have this great move that I call 'The Walrus', where I just lie on top of my opponent and do nothing. (sic)"
Meanwhile, Elon announced the rebrand of his social media platform in July, confirming that Twitter was being renamed X.
The businessman - who is also the CEO of Tesla - explained: "Twitter was acquired by X Corp both to ensure freedom of speech and as an accelerant for X, the everything app. This is not simply a company renaming itself, but doing the same thing.
"The Twitter name made sense when it was just 140-character messages going back and forth - like birds tweeting - but now you can post almost anything, including several hours of video.
"In the months to come, we will add comprehensive communications and the ability to conduct your entire financial world. The Twitter name does not make sense in that context, so we must bid adieu to the bird. (sic)"