COVID-19 and hepatitis B virus (HBV) infection cause serious public health problems. The management and follow-up of co-infection with these diseases is uncertain. İmmunosuppressive therapies used during the treatment of COVID-19 disease can cause HBV reactivation(HBVr). This study sought to determine HBVr incidence, risk and rate in COVID-19 patients receiving corticosteroids. Between 1.March.2020 and 1.January.2022, in patients with positive HBsAg and/or anti-HBc-IgG tests who were hospitalised for COVID-19, the dose and duration of systemic corticosteroids used, pre/post-treatment haemogram, liver function tests, ELISA and HBV DNA tests, and mortality were evaluated. During the study period, there were 13673 hospitalisations for COVID-19 infection and 184 deaths(1.34%). 145 patients (125 HBsAg[+], 20 HBsAg[-]/anti-HBc-IgG[+]) were included in the study. Fourteen patients died from COVID-19-induced respiratory failure, mortality 9.6%. Mortality was proportionally higher compared to COVID-19 infection without HBV. Seventy-five(51.7%) patients received methylprednisolone. The median dose of methylprednisolone used was 520(240-1400) mg, and the median duration was 6(4-10) days. HBVr developed in 7 of the patients. The days and doses of steroid use were significantly higher in patients who developed reactivation compared to the group who did not develop reactivation (Methylprednisolone; day 8[2-25], 0[0-6], p=0.007, total dose 440[80-2620], 0[0-400], p=0.021). Chronic hepatitis B treatment was initiated in 5 patients with HBVr and 2 patients had exitus.Corticosteroid treatments used during COVID-19 treatment may cause HBVr. According to the results of our study, patients who will be given steroid treatment should be examined for HBV co-infection, and high-risk patients should be carefully monitored for HBVr.