Grave of the Fireflies is a 1988 Japanese animated war film written and directed by Isao Takahata. It stars the voices of Tsutomu Tatsumi, Ayano Shiraishi, Yoshiko Shinohara [ja], and Akemi Yamaguchi [ja]. Based on Akiyuki Nosaka's 1967 semi-autobiographical short story of the same name, the film is set in Kobe shortly after its bombing by the U.S. Army Air Forces, and follows two orphaned siblings who desperately struggle to survive during the final months of the Pacific War.

Production began after Nosaka became interested in an animated adaptation of his book. It was animated by Studio Ghibli, marking Takahata's first film with the studio. Several critics considered it an anti-war film, but Takahata disagreed. The film was theatrically released in Japan by Toho on April 16, 1988, and was a modest success at the Japanese box office, grossing ¥1.7 billion. Its later international releases between 2018 and 2025 grossed $4.7 million overseas. It received universal acclaim and is considered by many to be Takahata's masterpiece, one of the greatest animated films of all time, and a major work of Japanese animation. It garnered particular praise for its emotional weight, and is often cited as one of the saddest films ever made.

In March 1945, American bombers destroy most of Kobe during the waning days of the Pacific War. Seita and his sister Setsuko, children of an Imperial Japanese Navy captain, survive, but their mother dies. She is cremated in a mass grave outside and Seita is seen carrying a small wooden box containing her ashes. Seita conceals their mother's death from Setsuko. The siblings move in with an aunt. He hides his mother's box of ashes in the garden. Seita retrieves a supply cache he buried before the bombing and gives everything to his aunt, save for a tin of Sakuma drops, which he gives to Setsuko. The aunt convinces Seita to sell his mother's silk kimonos for rice, which devastates Setsuko.

As rations dwindle, the aunt becomes resentful of the children as Seita does nothing to earn the food she prepares for them. At her suggestion, Seita withdraws some money from his mother's bank account to buy a charcoal stove and other supplies. Following an air raid, the siblings move into an abandoned bomb shelter. Among the belongings is the wooden box of his mother's ashes. They capture fireflies from the marshes and release them into the refuge for light. The following morning the fireflies have died. Setsuko buries them and reveals their aunt told her their mother died, then tearfully asks why the fireflies had to die so soon.

The situation becomes dire when they run out of rice. A friendly farmer recommends that Seita swallow his pride and return to his aunt, but he refuses, instead stealing crops from farms and breaking into homes during air raids. A farmer catches him and brings him to the police station, but the sympathetic policeman lets him go.

Setsuko falls ill, and a doctor explains she is suffering from malnutrition. Seita withdraws the last of the money from their mother's bank account. He is distraught to learn that Japan has surrendered and that his father is most likely dead, as most of Japan's naval fleet has been sunk. Seita returns to Setsuko with food and finds her hallucinating. She dies as Seita finishes preparing the food. Seita cremates Setsuko's body and her doll in a straw casket. He carries her ashes in the candy tin along with his father's photograph.

Seita dies of starvation a few weeks later at a Sannomiya train station surrounded by other malnourished people. A janitor, tasked with removing the bodies before the Americans' arrival, sorts through Seita's possessions. He finds the candy tin and throws it into a field. Setsuko's ashes spread out, and her spirit springs from the container, joined by Seita's spirit and a cloud of fireflies. The two board a ghostly train and, throughout the journey, look back at the events leading to Seita's death as silent, passive observers. Their spirits, healthy and content, arrive at their destination: a hilltop bench overlooking present-day Kobe, surrounded by fireflies.

"Grave of the Fireflies" author Akiyuki Nosaka said that many offers had been made to make a live-action film adaptation of his short story. Nosaka argued that "it was impossible to create the barren, scorched earth that's to be the backdrop of the story". He also argued that contemporary children would not be able to convincingly play the characters. Nosaka expressed surprise when an animated version was offered. After seeing the storyboards, Nosaka concluded that it was not possible for such a story to have been made in any method other than animation and expressed surprise in how accurately the rice paddies and townscape were depicted. Although the film deals with World War II, with the exception of Isao Takahata, most of the key staff members belonged to a relatively young generation that had not experienced the war firsthand. When Nizo Yamamoto was approached by Takahata to serve as art director, he initially intended to decline, reasoning, "Wouldn't someone who experienced the war and knows the conditions of that time be better able to depict it realistically?" However, Takahata reportedly persuaded him by saying, "It is precisely because you don't know the war that I want you young people to do this". Takahata drew from his personal experience to create a realistic depiction of the air raid on Okayama. He criticized TV shows and movies that had recreated images of incendiary bombs, "They include no sparks or explosions, I was there and I experienced it, so I know what it was like."