Using internet has a growing popularity, especially among students. The aim of this study was to determine the prevalence of internet addiction and its relationship with the level of self esteem and life satisfaction in students of lorestan university of medical sciences in Iran. A cross-sectional study, with applying stratified sampling and then multi-stage cluster sampling method was performed. The sample size was 160. Four questionnaires (Demographic characteristics, Internet Addiction Test (IAT) by Dr. Kimberly Young, Rosenberg's Self esteem Scale and Diener’s Life Satisfaction Scale) were used to collect data, the software spss 16 was used for data analysis. Prevalence of internet addiction was 10%, and this problem was more prevalent in male students (P˂0.05). Moreover, there was a significant and adverse relation between internet addiction score and self esteem score (P=0.015), and life satisfaction score (P=0.012). There was a significant and direct relationship between life satisfaction and self esteem (P=0.001). Young people should be encouraged to use the internet as a more useful and efficient tool and become aware of the internet and its harmful effects.
