Eva-00 Prototype Unit. The very first Evangelion built at NERV HQ. It was originally orange and lacking shoulder units, however after sustaining extreme damage in Evangelion Episode 06 it was upgraded to operational status, had shoulder units added, and painted blue.

Eva-00's dedicated pilot is the First Children - Rei Ayanami. The soul that dwells within Eva-00 is something of a mystery. Eva-01's soul is that of Yui Ikari, Shinji Ikari's (Eva-01's pilot's) mother. Likewise Eva-02's soul is that of Sohryu Kyouko Zeppelin, Asuka Langley Sohryu's (Eva-02's pilot's) mother. Rei is special, she is without a mother in the normal sense, and thus determining whose soul is within Eva-00 is difficult. Like many things in Neon Genesis Evangelion there is no correct answer to this mystery. One theory that has been proven to be false is that Eva-00's soul belongs to Naoko Akagi, Ristuko Akagi's mother.

Eva-00 was destroyed, along with the second incarnation of Rei, in Evangelion Episode 23. Rei reversed Eva-00's A. T. Field and drew the 16th Angel to her in an effort to save Shinji and Eva-01. She then self-destructed Eva-00, destroying herself, Eva-00, the 16th Angel and much of Tokyo-3.