This paper attempts to examine the date of Acts by presenting three reasons, pointing out that the book would be written in the early second century C.E. First, the word “Christian” (christianos) occurs but three times in the New Testament. It only occurs once in 1 Peter besides in Acts. It was not widely used until the end of the first century or the beginning of second century. That is, until then Christians did not generally call themselves as “Christian.” Accordingly, the fact that it occurs twice in Acts implies that the book was written around the end of the first century or later. Second, according to Acts, a silversmith, who made silver shrines of Artemis, shouted that Paul “led astray large numbers of people in Ephesus and in practically the whole province of Asia and there was danger that their trade would lose its good name.” This incident could not have taken place during Paul’s lifetime, because the followers of Paul in Ephesus were estimated no more than 200 people. What the silversmith said reveals the situation of the early second century. So it is reasonable to date the composition of the Acts to the early second century. Third, there has been a general consensus that Luke and Acts were written by the same person and that Stephen at the moment of his martyrdom repeated the words that Jesus had spoken from the cross. But Jesus’ words “Father, forgive them, for they do not know what they are doing” are not found in the autograph of the Gospel of Luke. This means that the author of Acts read the corrupted text of the Gospel of Luke. and hence the Gospel of Luke and the Book of Acts could not have been written by the same author. Therefore it seems natural to conclude that the Acts of Apostles would be written in the early half of the second century.