Frecuencia de marcadores serológicos del virus de la hepatitis B en sujetos fallecidos en un hospital clase A de San JoséObjective: To determine the frequency of three serological markers of Hepatitis B virus (HBV) in a series of corpses in a Class A general hospital of Costa Rica. Material and Methods: Using ELISA and RIA methods, three serological markers of HBV were investigated in the serum of the corpses. Results: HBsAg was found in 2.4% of the deceased, anti-HBs in 29.8%; and anti-HBc in 31.8%. Conclusions: The frequency of the markers studied was relatively high in this sample, in comparison with rates in blood donors and other population groups in the country. Similar studies of hospitalized deceased persons were not found in the world literature. The present study suggests that infection with HBV is more common in nosocomial populations.