Addiction to and problematic use of the Internet are relatively recent phenomena whose scope, characteristics and correlates have begun to receive increasing attention by clinicians and researchers alike. The purpose of this study was to examine the relationship between time spent connected to the Internet and the variables that indicate a pathological and addictive use of this technological resource. The sample was comprised of 1,301 university students of both sexes (927 women and 374 men), with ages ranging from 18 to 30 years old. The results showed that, although most people use the Internet appropriately, users who invest higher quantities of time in the Internet more frequently exhibit connection behavior that is controlled through negative reinforcement, a high degree of arousal when online, loss of control over connection behavior, changes in health-related habits, and interference in the social, family, academic, or work spheres. These findings suggest that excessive Internet use is associated with the onset of several problems that are similar to those associated with other behavioral and technological addictions.