To analyze the role of Haemophilus influenzae type b in children's death resulting from severe pneumonia conventional PCR, Southern blotting and in situ PCR were evaluated for the detection of Hib in 202 paraffin-embedded lung tissue autopsy samples from children with fatal outcome of pneumonia in China during the period of 1953-2002. The results indicate that Hib was a cause of fatal pneumonia in 36 (17.8%) of 202 samples.