Isao Takahata was the only living animator involved on the project who had survived bomb blasts.

Produced concurrently with My Neighbor Totoro (1988). Many of the animators had trouble remembering which film they were animating.

In South Korea, the release of the movie was postponed indefinitely because of the concern that the movie somewhat justified Japan's role in World War II.

This film was initially distributed with My Neighbor Totoro (1988) because it was the only way that Miyazaki could have been able to make "Totoro." The reason being that the original film pitch for that film was rejected, so they pitched a double feature with "Grave of the Fireflies," and the project was eventually backed financially by the original writer of the book on which "Grave" is based. It often was overlooked as a film because whenever "Totoro" was screened first, people were left happy and did not wish to be saddened by "Grave" afterward.

NTV in Japan produced a live-action version of "Grave of the Fireflies" in celebration of the 60th anniversary of the end of World War II. The made-for-TV movie Grave of the Fireflys (2005) began airing on November 1, 2005, at 21:00 Japanese time. Like the animated version, the movie focuses on two siblings and their struggle to survive the final days of the war in Kobe, Japan. However, unlike the animated version, the movie tells the story from the point of view of their aunt, and it deals with the issue of how a wartime environment could change a kind woman into a cold-blooded demon. That version stars the famous Japanese celebrity and actress Nanako Matsushima as the aunt.

The fruit drops that Setsuko eats were made by the Sakuma Confectionary Company, which in real life was established in 1949 (four years after the events in this movie took place). A few years ago, Sakuma released limited edition tin cans that resembled the one seen in the movie. Some variations of these tins also had a picture of Setsuko looking through her tin for the last drop.

From the start of production, director Isao Takahata wanted to cast appropriately aged children in the roles of Seita and Setsuko. Because the film takes place in Kobe, the search was limited to the Kansai region of Japan in order to find children who spoke the proper dialect. He was introduced to Ayano Shiraishi through a regional children's acting company, and he decided to cast her as Setsuko after only hearing two sentences: "My name is Ayano Shriraishi. I am five years old." He was later told by one of the company's leaders that they expected that Ayano was too young for the role, and so those were the only lines she had been instructed to recite in the audition.

This is the only Ghibili theatrical feature film to not be part of the Disney-Tokuma deal.

Roger Ebert of the Chicago Sun-Times considered it to be one of the best and most powerful war films and, in 2000, included it on his "Great Movies" list.

The movie was originally intended as a sort-of double feature with another Ghibli movie, My Neighbor Totoro (1988). Ghibli's parent company reasoned that Totoro's tie-in with a movie with more educational merit would guarantee its inclusion in the list of summer's recommended movies for school children.

Most of the illustration outlines in the film are in brown, instead of the customary black. Whenever black was used, it was only used when it was absolutely necessary. Color coordinator Michiyo Yasuda said this was done to give the film a softer feel. Yasuda said that until that point it had never been used in an anime before, "and it was done on a challenge." Yasuda explained that brown is more difficult to use than black because it does not contrast as well as black.

According to the movie, the children's father was a captain in the Imperial Japanese Navy (IJN) who served aboard the Maya, a Takao-class heavy cruiser which participated in a number of naval engagements during the Second World War. On 23 October 1944, during the Battle of Leyte Gulf, Maya was torpedoed by an American submarine and sank with the loss of 479 men, including the ship's captain. The ship's name is derived from Mount Maya, a mountain located near the city of Kobe, which is where the movie takes place.

Director Isao Takahata repeatedly denied that the film was an anti-war film. In his own words, "[The film] is not at all an anti-war anime and contains absolutely no such message." Instead, Takahata had intended to convey an image of the brother and sister living a failed life due to isolation from society and invoke sympathy, particularly in people in their teens and twenties.

The film is included on Roger Ebert's "Great Movies" list.

Included among the "1001 Movies You Must See Before You Die", edited by Steven Schneider.

StudioCanal re-released the film on 17 May 2013 in the UK with My Neighbour Totoro (1988) as a double-bill. StudioCanal will always have the rights to bring Ghibli films to the UK.

The film was released on 16 April 1988, over 20 years from the publication of the short story.

Isao Takahata: The patient who comes in to see the doctor after Setsuko.

The film is based on a true story. Akiyuki Nosaka lost his little sister during the war to malnutrition and blamed himself for her death. He wrote "Hotaru no haka" ("A Grave of Fireflies") in 1967 to come to terms with the loss.