Although researchers have studied problematic Internet use for almost a decade, there is a dearth of quantitative models to describe this phenomenon. We aimed to create a structural equation model by which we explored the extent to which the functions of the Internet use, cognitive absorption, and depression affected and explained an individual's problematic Internet use. In 2011 and 2012 years, 244 high school students (117 boys and 127 girls) participated in this study to complete the Problematic Internet Use Scale, the Cognitive Absorption Scale, the Beck Depression Inventory, and the Internet Use Function Questionnaire. We found that the students' functions of Internet use, cognitive absorption, and depression explained the problematic Internet use to some extent. (C) 2014 Elsevier Ltd. All rights reserved.