By using the history of ideas, this paper explores John 6, the Eucharist and the Dionysus cult by looking into the relationship between them. In the modern study of the Eucharist, the most important three scholars (Hans Lietzmann, Gregory Dix, and Joachim Jeremias) have investigated many areas of the Eucharist: its origin, development, function, ritual format, and historical debate on it. However, regarding the Johannine Eucharist, their interests are insufficient and unfair compared to their focuses on the Synoptics and Paul. In this regard, Gregory Riley and Stephen Need have indicated that John`s Eucharist is fundamentally different from Paul`s Eucharistic doctrine and the Synoptic`s. In particular, Riley suggests the shadow of the cult of Dionysus over John`s Eucharist. In his connection to wine, Dionysus is perceived as a wine god and his epiphany is closely related to wine miracles in many places. Wine has a crucial religious value in creating a path to communion with the god, providing a religious ecstasy. The unique ritual of the Dionysus cult was held in orgy where the participants tore (sparagmos) and ate the raw flesh (omophagia) in order to intake the god`s power. This Dionysiac feature mostly appears in John`s Jesus who turns water into wine as does Dionysus, and identifies himself as grape vine (15:1-11). The significant influence of Dionysus on Christianity is the “concept of Dionysos as the suffering Son of God”, which is obvious in the Euripides` Bachae where a violent Pentheus unjustly persecuted the Son of God (Zeus). The literary structure and themes in John 4:5-30 and 6:16-59 exhibit the influence of Dionysus as well. The dialogue between Jesus and the Samaritan woman recalls the dialogue between Dionysus and the shepherd in 4:5-30, which functions to interpret John 6 in the Dionysiac image. Jesus` walking on the water discourse (6:16-21) reinforces this Dionysiac motif so that it serves to introduce the bread of life discourse (6:35-48) and the Eucharistic words (6:51-59). In this aspect, unlike the Synoptics and Paul`s descriptions, John`s Eucharist reflects the Dionysiac influence because it replaces the term “body” with “flesh” and indicates Jesus` flesh and blood are real food for everlasting life in cannibalism. In the case of cannibalism, Dionysus is both the raw flesh eater and a victim of cannibalism at the same time and the two features are not clearly separated in him. The author of John, however, revaluates cannibalism in positive terms by imparting life through Jesus` flesh and blood. Therefore, the Johannine Eucharist is influenced by the Dionysus cult in Greco-Roman religion, which provides new perspectives for the interpretation of John`s Eucharist as well as Christian origins.