Objective The aim of this study was to determine the relationship and mutual effects between online gambling addiction and loneliness in young adults studying at a public university in Türkiye. Material and Method This study was designed in a cross-sectional style and prepared with the information collected by the survey application method. The study population was made up of young adults studying at a public university in Türkiye. The data were obtained in December 2021 using an in-person data collection method with two questionnaire forms containing demographic data, Online Gambling Addiction Scale (OGAS) and Social and Emotional Loneliness Scale for Adults (SELSA-S). Results There were a total of 449 university students participated in the study. Of them, 52.8% were females. Those who were addicted to online gambling constituted 35.0% of the group, and those who were addicted to young adults gambling had significantly higher loneliness than those who were not (p=0.005). Conclusion In young adults, loneliness has been shown to have a predictive effect on online gambling addiction.