Angel Beats! is an original TV anime (not based on a pre-existing game) produced through a joint project between Key, Aniplex, Dengeki G's Magazine and P.A.WORKS, with story and screenplay by Key writer Jun Maeda and character design by Na-Ga, both working on their first TV series.

The title logo's bottom decorative line was designed to evoke a musical beat or a heartbeat pulse signal, meant to look good on packaging and merchandise.

Several voice actors were cast on Jun Maeda's personal recommendation.

Yuzuru Otonashi's voice actor Hiroshi Kamiya was chosen because his audition performance most delicately captured the confusion of someone who had just arrived in the afterlife, fitting the concept of Otonashi as a life-sized, ordinary high schooler.

Kana Hanazawa was cast as Kanade partly because her voice could distinguish the character's quiet, dimwitted-but-not-gloomy persona from Yusa, another near-silent, flat-toned character.

Yui's seiyuu Eri Kitamura was chosen because her audition conveyed real intensity in the character's irrational outbursts, fitting Yui's hot-tempered, airheaded personality.

The school building's design is reportedly modeled on Kanazawa University, and an illustration drawn for the anime was used on a poster for an academic conference held at the university's Kakuma campus in 2011.

The name Yuri is said to be inspired by Yuri Nakamura, vocalist of the band GARNET CROW, since both share the nickname 'Yuripe' and Jun Maeda, a fan of the band, quoted their single 'Futari no Rocket' as the title of the first chapter of the Angel Beats! novel.

The character TK speaks almost entirely in lines inspired by or quoting the band TM NETWORK; his name is believed to derive from Tetsuya Komuro's initials, reflecting Maeda's strong admiration for TM NETWORK.

At Maeda's request, the show's score was composed using minimalist music, an unusual genre choice for anime background music, composed by Maeda himself along with the duo ANANT-GARDE EYES.

Noda's weapon was originally planned to be a simple club, but it was changed to a halberd specifically to allow a scene where he holds a blade to Otonashi's throat.

The theme song single 'My Soul, Your Beats!/Brave Song' topped Oricon's anime/voice-actor category for 2010 and won Billboard Japan's 'Billboard JAPAN Independent of the Year 2010' award, while the soundtrack album charted unusually high on TV programs like Count Down TV for an anime OST.

Jun Maeda later revealed in a magazine that the 'Another Epilogue' bonus ending was actually his originally intended finale, featuring a twist suggesting a time loop and that Otonashi himself created the shadows, but the director rejected it as not being a happy ending, forcing Maeda to rewrite the broadcast Episode 13 ending.

After the alternate ending aired, fans debated online the apparent inconsistency between the epilogue shown in the TV broadcast and the Blu-ray/DVD 'Another Epilogue', particularly whether Otonashi reincarnated immediately afterward.