Tokyo is to host the world premiere of the fifth Harry Potter film, The Order of the Phoenix, on 28 June.
Potter faces his arch nemesis Lord Voldemort in the film
The Japanese capital was chosen after another highly-anticipated sequel, Spider-Man 3, opened there and broke box office records.
But a Warner Brothers spokeswoman said there was "no special reason" for opting to launch the film in Japan.
The UK premiere of the film, which stars Daniel Radcliffe, will be held in London on 3 July.
The four previous Harry Potter movies, based on JK Rowling's books, have grossed more than $3.5bn (£1.7bn) worldwide.
Harry Potter and the Deathly Hallows, the seventh and final book in the series, will go on sale on 21 July, but it is not clear when the film version will be made.
Spider-Man 3, starring Tobey Maguire, notched up one of the highest-ever openings at the UK box office when it opened earlier this month, despite mixed reviews.