Picnic at Hanging Rock is a 1975 Australian mystery film directed by Peter Weir and based on the 1967 novel Picnic at Hanging Rock by Joan Lindsay. Cliff Green adapted the novel into a screenplay. The film stars Rachel Roberts, Dominic Guard, Helen Morse, Vivean Gray and Jacki Weaver. The plot involves the disappearance of several schoolgirls and their teacher during a picnic at Hanging Rock, Victoria on Valentine's Day in 1900, and the subsequent effect on the local community.

Picnic at Hanging Rock was a commercial and critical success, and helped draw international attention to the then-emerging Australian New Wave of cinema. It is widely regarded as one of the most iconic and defining films of the New Wave. In 1996 it was voted the best Australian movie of all time in a poll by the Victorian Centenary of Cinema Committee and the NFSA.

In 2025 the film was restored for release into cinemas. Under the supervision of Peter Weir, a new 4K scan of the original 35mm negative (from the National Film and Sound Archive in Australia) was undertaken by The Grainery (USA) and Fixafilm(Poland). Coincident with the release, Text Publishing issued the biography of Joan Lindsay by Brenda Niall which describes Lindsay's school experience evident in the mystery at Hanging Rock, its significance in the landscape and its resonance for First Nations, people. Niall considers both Lindsay's novel and later contribution to the making of the film.