In the perspective of missional hermeneutics, the Book of Revelation is the conclusion of mission while Genesis is the beginning of it. This book needs to be understood as a supportive missionary document as it was given to the Christians of the 1st century to keep the confession of faith, “Jesus is the Christ” and to win in the midst of persecution. The purpose of this dissertation is to examine the witness in the Book of Revelation from the viewpoint of missional hermeneutics, so as to understand the whole of the Book as Missio Dei. "Two Witnesses" in Chapter 11 who represent the theology of witness were martyred during the their prophecy in power, and their blood, through the resurrection of the two witnesses and the repentance of many, leads to victory, not defeat. The witness in this book, ‘’ shows the faith of worship, mission, and martyrdom which run through the Book of Revelation overall. Jesus himself is introduced as 'the faithful witness,' and John, the author, also introduces himself as one to the word of God and Jesus, and all churches are called witnesses along with the seven churches. The faith of witness flows into universal missionary work for every tribe, people, language and nation and Babylon the great that refuses the testimony is subject to eternal judgement whereas the churches, the community of the witnesses, enter in a new heaven and a new earth.