The main purpose of this study is to investigate the relationship between loneliness and smartphone addiction of students studying at the faculty of sports sciences. The study was conducted with the correlational survey method. The study group consisted of a total of 281 students, 61 females (21.7%) and 220 males (78.3%). In the study, Mobile telephone addiction scale developed by Sar, Ayas, and Horzum (2015) was used to investigate the mobile phone addiction levels of the participants. Loneliness scale developed by Demir (1989) was used to measure loneliness levels. According to the results of the study, there was no statistically significant difference between loneliness and smartphone addiction of students according to gender and academic achievement variables. On the other hand, there was a significant difference between loneliness and smartphone addiction according to the departments of the students. Looking at the relationship between loneliness and smartphone addiction levels, it was concluded that there was a statistically significant positive correlation between all sub-dimensions of smartphone addiction and smartphone addiction total score.