Secondary problems as a result of internet use are becoming common at young age. Research related to factors that influence internet problems continues to be carried out to develop internet problem strategies such as Islamic religious coping and emotion regulation difficulties. The purpose of this study is to identify the effect of Islamic religious coping on problematic internet use (PIU) with emotion regulation difficulties as a mediating variable. This study used a quantitative approach with 304 Muslim undergraduate students in Indonesia as respondents. The measuring instruments used were Iranian Religious Coping (IRCOPE), Difficulties in Emotion Regulation Scale-18 (DERS-18), and Generalized Problematic Internet Use Scale 2 (GPIUS 2), which had been adapted into the Indonesian language. The results of the path analysis technique showed an effect of Islamic religious coping on emotion regulation difficulties and problematic internet use. However, there was no effect of Islamic religious coping on problematic internet use. This indicates that emotion regulation difficulties can fully mediate the correlation between Islamic religious coping and problematic internet use.