This study aimed to determine whether problematic internet use and healthy lifestyle behaviors among high school students varied by gender, grade level, academic average, and school type variables and to investigate the relationship between problematic internet use and healthy lifestyle behaviors. The sample of the study consisted of a total of 310 students enrolled in three different high schools in Giresun province in Turkey, including 159 females and 151 males. The study employed the relational screening model. The data collection tools used in the study were the Problematic Internet Use Scale (PIUS), the Healthy Lifestyle Behaviors Scale (HLBS) and a Personal Information Form. Independent group t-test, one-way variance analysis, and Pearson product-moment correlation coefficient were utilized in the analysis of the data. The results of the study indicated that problematic internet use varied by grade level, academic average, and school type variable, it did not show a difference according to gender and whether parents live together or apart variables, and that healthy lifestyle behaviors did not show any difference according to any variables at all. In the study, a low negative correlation was found between problematic internet use and healthy lifestyle behaviors. The findings of the study were interpreted and discussed in light of related literature.