At the end of 2019, COVID-19 (SARS-CoV-2) has become a global pandemic with severe acute respiratory syndrome. The virus started from Wuhan, China on 29 December 2019 and spread widely all over the world in a short period. The present review reports the activity of one striking lichen; Cetraria islandica (L.) Ach. as probable complementary effective treatment for symptoms associated with Covid-19, infection. Many potential treatments have been introduced, which are considered potent antiviral drugs and commonly reported as herbal or traditional and medicinal treatments. Currently, several studies confirmed that herbal medicine plays a major role in the prevention and treatment of many diseases also for the novel coronavirus. As well as, the post-COVID syndromes which have been detected in many people who've "recovered" from COVID-19 but still suffering from its pulmonary symptoms. In the light of findings reported in the present study, C. islandica supplements can add a significant role to protect lung from COVID-19 symptoms and post-COVID syndrome alongside with synthetic drugs or vaccines. Therefore, C. islandica supplements have the potential of being utilized as novel bio-resources for naturally occurring phytotherapies.