The term mobile portfolio refers to creating, evaluating and sharing portfolios in mobile environments. Many of the states that pose an obstacle for portfolio usage are now extinguished through mobile portfolios. The aim in this research is to determine the effect of mobile portfolio supported mastery learning model on students' success and attitudes towards using internet. The research was carried out in the Academic Year 2014-2015 with students, taking Computer-I course at Primary School Teacher Education and Social Sciences Teaching Departments in Faculty of Education in Siirt University. The Internet Usage Attitudes Scale developed by Tavsancil & Keser (2002), was used to determine student attitudes towards internet usage. The scale was prepared as a five point Likert type scale. An academic achievement test developed by researchers was used to determine achievement of course. The data analysis methods used in this study were average, standard deviation, independent groups t-test and dependent groups t-test. As a result of research, the effect of mobile portfolio supported mastery learning model on students' academic achievement was found to be positive. Furthermore, use of mobile portfolio among students tested in research, a positive increase was seen in their attitudes towards internet use. As a result of the data analysis, this difference shows no significant difference. According to the findings recommendations have been made.