Background: Olfactory neural epithelium and olfactory filae can regenerate, making them potential candidates for therapeutic intervention in individuals with olfactory impairment. Platelet-rich plasma (PRP) is an autologous biologic product made from freshly obtained whole blood that has a high platelet content. In a variety of therapeutic contexts, it has been utilized as a secure and effective treatment for peripheral neuropathies, inflammation, and wound healing. The aim of this study was to assess the potential therapeutic effect of platelet-rich plasma (PRP) in the treatment of post-COVID-19 anosmic patients. Methods : This prospective study was conducted in the Otorhinolaryngology Department outpatient clinic at Zagazig University. Included 36 patients all of them were complaining of complete loss of smell (anosmia) post (COVID 19). Experimental group: included 18 patients Platelet-rich plasma preparation. Control group: included 18 patients received placebo. Results: Incidence of complete anosmia improvement in experimental group was 77.8% versus 11.1% in control group with relative improvement seven times, p<0.05. There was no significant difference of VAS score between groups in after first dose, p>0.05. There was no significant difference of VAS score in control group up to (6 weeks) follow p>0.05. Yet, there was significant decrease of VAS score in control group after (8 weeks) follow up, p<0.05.There is significant and inverse association between platelet count, and mean anosmia score in both group, p=0.0001. Conclusion: An injection of platelet-rich plasma into the olfactory cleft may be beneficial for patients with post-COVID-19 olfactory anosmia who did not respond to traditional conservative treatment.