In 200 forensic autopsies, which had been randomly selected, the accuracy of macroscopic diagnosis of alveolar pneumonia was controlled by histological follow-up examination. Only 11 out of a total of 14 cases of alveolar pneumonia, which had been diagnosed macroscopically, could be confirmed microscopically. Moreover, histological examination revealed ten other cases of alveolar and one case of interstitial pneumonia. The rate of wrongly diagnosed cases of alveolar pneumonia was 47.6 per cent, of the total number of cases (200) it was 6.5 per cent. Most cases with confirmed pneumonia belonged to a risk group (survival time of more than 24 h, drug addiction, HIV-infection, alcohol abuse, homelessness), where the frequency of alveolar pneumonia was 23.5 percent. An increased weight of the lungs correlated with the frequency of pneumonia. A point system was developed by taking into account predictive factors in pneumonia. By reaching a certain number of points histological examination should be performed, which considerably improved diagnosis of pneumonia.