With the increasing development in information technology, also the conveniences, interests and privacy of internet, made many children hard to stay away from, and deeply addicted to it. Due to excessive use of the internet, the results show many elementary children appear to have Internet addiction symptoms. Not only affecting their daily lives, but also damaging their personal health as well. The purpose of this study is to understand Internet addiction of senior grade students in elementary schools, and their interpersonal relationship status in Kaohsiung city. Also discussing the differences between different gender, grade, family structures, years of Internet experience, times spent online weekly, the main purpose and places, such background variables in Internet addiction, as well as elementary children‟s Internet addiction and interpersonal relationship. Clustering sampling method and simple random sampling surveys were used in this study, which were drawn out from 16 classes through 8 different schools, a total of 450 samples among elementariness‟ students. The main results include the proportion of the high Internet addiction group and the mid-Internet addiction group, significant difference in pupils who log online from different places, among these places, logging online in Internet cafés shows seriousness results of internet addiction. Moreover, there is significant correlation in interpersonal relationship with Internet addiction.