To assess the safety and immunogenicity of influenza vaccination, patients with cirrhosis undergoing treatment or not and liver transplant recipients under standard immunosuppression were vaccinated and followed up for 6 months. One month after vaccination, seroprotection rates and antibody GMTs against the three vaccine antigens were higher than baseline levels in all three patients groups. No differences in seroconversion and seroprotection rates were found within groups, but antibody GMTs against A/H1N1 and A/H3N2 strains were lower in liver transplant recipients than in patients with cirrhosis without treatment. No serious adverse events and no alteration of the liver function tests were observed. Patients with cirrhosis, including those under treatment, and liver transplant recipients benefit from influenza vaccination and can be safely immunized.