Background & Aims: World Health Organization declared COVID-19 as a pandemic. Lockdown and distance from normal social activities led to widespread increasing popularity of social networks. Meanwhile, fear and anxiety increased among social media users. The aim of this study was to systematiclly review the factors associated with fear of COVID-19 among social media users. Materials & Methods: We searched the study keywords in Scopus, PubMed, Web of Science, and ScienceDirect databases and all related original articles till August 2021 were reviewed. A total of 172 related articles were identified, which after deleting duplicates (28), and screening titles and abstracts (107), the full texts of 37 residual studies were evaluated for eligibility and inclusion criteria, znd 25 articles included in this review. Results: The summary of review articles showed that using social media during the COVID-19 pandemic era was directly associated with the spread of panic and fear. The most used social media were Facebook, WhatsApp, Instagram, Twitter, YouTube, Telegram, LinkedIn, TikTak, Skype, Zoom, Weibo, TV, and government sources. The impact of social networks on panic in crucial periods depends on age, gender, education, and culture. The results of this systematic review showed that females, married persons, people with a history of anxiety, depression, physical and chronic illness, as well as those whom did not exercise regularly, felt more panic than others. Following medical pages on social media as well as reposting and sharing COVID-19 information on social media could cause more fear. Conclusion: Although, social media can play a pivotal role in raising public awareness and overcoming COVID-19 limitations by reducing risk perception, strengthening social relationships, and preventing fear of shopping during quarantine days by developing online shoppings, but may indirectly spread fake reports and increase anxiety.