The rapid development of information technology, such as the Internet and social networks, lead to an increasing number of online relationships in the world and caused some problems for families and society. One of these problems is extramarital relationships that occur through the Internet and social networks. The purpose of this study was to investigate the relationship between marital quality and Internet infidelity by considering the role of loneliness. Participants comprised a total of 406 (190 female and 216 male) married persons, who responded to Social and Emotional Loneliness Scale for Adults (SELSA-S), Internet Infidelity Questionnaire (IIQ), and Revised Dyadic Adjustment Scale (RDAS). The structural model showed that marital quality has negative correlation with loneliness and online infidelity and loneliness has positive correlation with online infidelity. Results also showed that loneliness has a mediating role in the relationship between marital quality and online infidelity.
