The prince spoke to the BBC ahead of the first Earthshot Prize, which looks to reward people with big ideas for saving the planet from catastrophic climate change.
Speaking about the current space race and the drive to promote space tourism, William said: “We need some of the world’s greatest brains and minds fixed on trying to repair this planet, not trying to find the next place to go and live.
“I think that ultimately is what sold it for me – that really is quite crucial to be focusing on this [planet] rather than giving up and heading out into space to try and think of solutions for the future.”
His comments come as Hollywood actor William Shatner became the oldest person to go into space this week, jetting off in a capsule built by billionaire Amazon founder Jeff Bezos.
The duke told Adam Fleming of BBC newscast that he had “absolutely no interest” in going to space, pointing out that there was a “fundamental question” over the carbon cost of space flights.