The music of the 1998 role-playing video game Parasite Eve, based on the novel of the same name by Hideaki Sena, was composed by Yoko Shimomura, and was one of her early popular successes. The music for its 1999 sequel Parasite Eve II was composed by Naoshi Mizuta and arranged by Hiroshi Nakajima. The 2010 spin-off title The 3rd Birthday was composed for by Shimomura, Mitsuto Suzuki and Tsuyoshi Sekito. Shimomura's work was described by herself as experimental, and incorporated multiple musical genres including opera music. The score for Parasite Eve was recorded at the Andora Studios in Los Angeles. For Parasite Eve II, Mizuta spent a year and a half on the project, using the game's scenario and visuals as references and taking inspiration from multiple film genres. It was Mizuta's first project after transferring from Capcom to Square Enix (then Square). For The 3rd Birthday, Shimomura worked with Suzuki and Sekito to create a score reminiscent of Parasite Eve, while Japanese rock band Superfly provided the theme song "Eyes on Me".
The original Parasite Eve Original Soundtrack album was released in May 1998 through DigiCube. Shimomura also produced an arrange album, Parasite Eve Remixes, which was released through DigiCube in July 1998. The soundtrack album for the second game, Parasite Eve II Original Soundtrack, was released through DigiCube in December 1999. It also released in North America through Tokyopop Soundtrax in September 2000. The third game's soundtrack album, The 3rd Birthday Original Soundtrack, released in December 2010 through Square Enix's music label. The first two game's original soundtracks were reissued through Square Enix in January 2010 due to popular demand, and a limited edition combined album titled Parasite Eve I & II Original Soundtrack Box was released alongside them. While some albums have received mixed responses from critics, the music of the Parasite Eve series has generally received positive reviews, with the score for the first game bringing Shimomura international acclaim.