The present study investigates the relationship between social self-efficacy, loneliness and internet addiction among Hashemite University students. It defines the level of social self-efficacy, and whether there are statistically significant differences by gender, academic specialization and academic level; and defines the levels of loneliness and internet addiction. The purposive sample consisted of (618) students at Hashemite University. The Social Self-efficacy, Loneliness and Internet Addiction Scales were used. The results show that the level of social self-efficacy was medium, with statistically significant differences in the level of social self-efficacy attributed to students by gender in favor of male students, and in the level of social self-efficacy by academic level in favor of second-year students. The level of loneliness was medium, as was the level of internet addiction. There was a negative correlation between social self-efficacy and loneliness and internet addiction, and a positive correlation between loneliness and internet addiction.