In fact, he's building a real-life version of the beautiful landscapes he has spent decades putting on screen in films such as Spirited Away and My Neighbour Totoro, in the form of a nature park for children, on an island off the coast of Japan.
The 74-year-old animator and director, who in 2013 was said to be retiring, has won acclaim and affection from film fans for creating animation classics with his studio, Studio Ghibli.
Japanese news site Kyodo reports that he will be funding the 300 million yen (£1.6 million) project himself, and that work will begin in April 2016, with a view to completion in 2018.
The "children's facility" will be built in a forest on Kume island in the Okinawa Prefecture. Miyazaki will replace existing playground equipment with an interactive site where children can enjoy nature through five senses.
Miyazaki's project has philanthropic roots. The filmmaker supported a programme started in nearby town Kumejima to help children who had been affected by the Fukushima nuclear disaster of 2011. A reinforced-concrete shelter that can house about 30 people will be part of the park.
The Oscar-winning filmmaker will donate the park to Kumejima when it is complete. But in the meantime, it will be built with a "made in Kumejima" ethos, making sure local construction materials are used and the opinions of citizens are taken into account.
As yet, there's no information as to whether Miyazaki's park will be open to adults who visit without children, but we suspect totoro will be granted free admission. Currently, the Studio Ghibli Museum in Mitaka, near Tokyo, offers a life-size model of a Catbus, the feline transport system seen in My Neighbour Totoro, among other exhibits.