Harry Potter and the Half-Blood Prince, the sixth movie in the box office hit franchise, selling an estimated $396.7 million worth of tickets during its first five days.
Warner Bros. Pictures said on Sunday it earned $159.7 million in the United States and Canada, the sixth-biggest five-day opening.
The previous record of $381.7 million was held by Spider-Man 3 in 2007.
The film cost $235 million to make, the most expensive one made in the franchise. Still, the franchise has been a lucrative one for the Time Warner Inc - owned studio, with the first five movies generating $4.5 billion in ticket sales worldwide since 2001.