Background/aim: The prevalence of hepatitis B infection is high worldwide with liver cirrhosis and hepatocellular carcinoma as important complications. Immunosuppression, especially from corticosteroids, is often cited as a cause of poor immune response and there is documented evidence of irrational administration of glucocorticoids to children and adults. Decreased expression of interleukin-4 and interferon-gamma is an indication of poor humoral and cellular immune responses, respectively. Therefore, we decided to find out if methylprednisolone injection decreases interleukin-4 and interferon-gamma expression following hepatitis B vaccination in mice. Materials and methods: Mice were randomly divided into 2 groups. Daily intramuscular injections of methylprednisolone (15 mg/kg) were given to the test group while water for injection (0.1 mL) was given to the control group for 30 days. On day 6 all mice were given 2 μg of hepatitis B vaccine and they received a booster dose on day 27. On day 34, blood samples were collected and analyzed for interleukin-4 and interferon-gamma titers. Results: There was positive interleukin-4 and interferon-gamma response in all groups but the differences in titers were not statistically significant. Conclusion: At the dosages and length of exposure used in this study, methylprednisolone injection did not significantly inhibit interleukin-4 and interferon-gamma expression following immunization against hepatitis B virus in mice.