Introduction and Importance: Coronavirus Disease 2019 (COVID-19) has become a pandemic since the beginning of 2020. COVID-19 is also spreading very rapidly in Indonesia and so far, no definitive therapy has been found. Case presentation We report two cases of confirmed COVID-19 with moderate pneumonia, who received 400 ml of convalescent plasma and showed improvements in clinical, laboratory and radiological examinations. Clinical discussion Passive immunotherapy is generally more effective when given early. Plasma transfusion is more beneficial when given before clinical conditions become severe. Some studies have shown that therapy with convalescent plasma can contribute to a longer survival and a lower length of stay. Conclusion Convalescent plasma can be used as an adjunctive therapy option for patients with moderate COVID-19.