This study executed questionnaire surveys on 482 undergraduates of D-college to review the extents of spam letter messages received through the mobile phones of college students and the extents of their addiction to mobile phones. It was revealed that each college student received one or two spam letter messages on average a day. Among the received spam messages were the messages containing the contents of commodity advertisements most frequent and the surveys indicated that spam messages are hardly read. As for the addiction to mobile phones, the average score of addiction of the respondents was indicated to be 38.73 based on the full score of 100 and the number of the ones with the scores of 60 or more was 47 which is 9.75% and the ones with the scores of 70 or more was 13 which is 2.70%. Also the younger the students were, the higher were the numbers of the students included in the addictive group and the number of students from other areas included in the addictive group was high and the number of the students in 2years system included in the addictive group was higher than the number of the students in 3years system included in the addictive group.