This study aims to examine the relationship between problematic internet usage and some demographic features among university students. Data was gathered from 342 female (63 %), 200 male (37 %), in total 542 university students. The Online Cognitive Scale (OCS) and Demographic Information Form were used for collecting the data. The time of connecting to internet was mostly at evening and the average of connection time was 0-9 hours per week. There were differences between the means of social comfort, loneliness/depression, diminished impulse control and distraction subscales of OCS according to gender and the age of onset of connecting to internet. Also, a high correlation coefficient was found between the frequency of internet use and the OCS. Females and males differed significantly in their use of internet as regards to the reasons. Internet usage changed according to the subjective evaluation of academic performance of students.