Harry Potter and the Prisoner of Azkaban is a 2004 fantasy film directed by Alfonso Cuarón from a screenplay by Steve Kloves. It is based on the 1999 novel Harry Potter and the Prisoner of Azkaban by J. K. Rowling. It is the sequel to Harry Potter and the Chamber of Secrets (2002) and the third instalment in the Harry Potter film series. The film stars Daniel Radcliffe as Harry Potter, alongside Rupert Grint and Emma Watson as Harry's best friends Ron Weasley and Hermione Granger respectively. It chronicles Harry's third year at Hogwarts and his quest to uncover the truth about his past, including the connection recently-escaped Azkaban prisoner Sirius Black has to Harry and his deceased parents.

With this film, the Harry Potter series switched to a longer eighteen-month production cycle. Cuarón was selected as director from a list that included Callie Khouri and Kenneth Branagh. The cast of previous instalments returned for the film, with the additions of Gary Oldman, David Thewlis, Timothy Spall, and Emma Thompson, among others. It was the first appearance of Michael Gambon as Professor Albus Dumbledore, due to Richard Harris's death in 2002. Principal photography began in February 2003 at Leavesden Film Studios. It was the first in the series to extensively use real-life locations, with sets built in Scotland and scenes shot in London. Filming wrapped in November 2003.

The film was released on 31 May 2004 in the United Kingdom, and on 4 June 2004 in North America. It was the first Harry Potter film to use IMAX Technology and released into IMAX theatres. Prisoner of Azkaban grossed a total of $808 million worldwide, making it the second-highest-grossing film of 2004, behind Shrek 2. Critics praised Cuarón's direction and the lead actors' performances. It is credited for marking a notable shift in the franchise's tone and directing style and is often regarded by critics and fans alike as the best Harry Potter film. It was nominated for two Academy Awards, Best Original Music Score and Best Visual Effects, at the 77th Academy Awards in 2004. It was followed by Harry Potter and the Goblet of Fire in 2005.