The aim of the present study is to investigate the role of motivational factors and personal characteristics on sharing of unconfirmed information by mediating social media fatigue in the time of COVID 19. This study is an applied study in terms of purpose and is a type of descriptive-correlational studies in terms of data collection method. Statistical population of the study consisted of all students at Semnan University in the academic year 2020-2021 that 230 people were selected as sample by stratified random sampling method. Study instrument included personal characteristics, motivational factors, social media fatigue and sharing of unconfirmed information questionnaires. Reliability of questionnaires using Cronbach's alpha, was respectively (0.91); (0.87); (0.70); (0.81). The results showed that Exploration, religiosity and poor self-regulation have no significant effect on sharing of unconfirmed information. Usage of social networks for entertainment and selfpromotion has a significant impact on sharing of unconfirmed information and social media fatigue. Social media fatigue has a significant impact on sharing of unconfirmed information. Exploration, religiosity, poor self-regulation, entertainment, self-promotion have an indirect effect on sharing of unconfirmed information of social networks through mediation of social media fatigue. The results indicate the importance of the role of motivational factors in social media fatigue and consequently sharing of unconfirmed information of social networks.