Former punk-band drummer Maezawa will join the 24 other astronauts who have flown beyond Earth's protective magnetic field, in missions between 1968 and 1972.
Mr Maezawa came to SpaceX with the idea for the group flight, Mr Musk said.
"One day when I was staring at his painting, I thought, 'What if Basquiat had gone to space and had seen the moon - what wonderful masterpiece would he have created?" "I would like to invite six to eight artists from around the world to join me on this mission to the Moon", he said.
Musk says he's aiming for Maezawa's moonshot to take place in 2023. It's expected that the Falcon will attempt at a test flight to Mars in 2022 and a manned mission to Mars by 2024. The BFR (Big Falcon Rocket) is being developed in a SpaceX facility at the Port of Los Angeles. "Usually there are many setbacks and issues", Musk said.
The tourism announcement comes as the company is racing to meet a tight deadline to start flying astronauts to and from the International Space Station aboard its workhorse Falcon 9 rocket and Crew Dragon spacecraft.More news: Christine Blasey Ford: Kavanaugh Accuser Comes Forward
The project is incredibly ambitious and expensive - the total development costs for BFR are somewhere between $US2 billion and $US10 billion, Musk said. It's envisioned as a base for exploration of the moon, Mars and beyond.
"All right. Maybe we will both be on it", Musk said to cheers and applause.
On top of all that, SpaceX said that the BFR will be 100 percent reusable, making the trip "economically feasible".
When the reporters asked Musk if he considered being a co-passenger, he did not rule out the possibility.
But Musk said, "This is the final iteration in terms of broad architectural design". Nevertheless, SpaceX is pressing on, and apparently feels confident enough in its work that it is comfortable parading its first paying private space "tourist" in front of the world.
SpaceX added that it was "an important step toward enabling access for everyday people who dream of travelling to space".
The BFR was first announced in 2016, and was touted as the most powerful rocket in history, even more potent than the Saturn V Moon rocket that launched the Apollo missions five decades ago.