The reliability and applicability of quantitative and qualitative diatom analysis by an enzymatic digestion method in the diagnosis of drowning of putrified bodies has been evaluated. The authors report the analysis of water and organ samples of 12 immersion cases using light microscopy. This study included control organ samples from the bodies of persons who died from causes other than drowning. Organ samples were treated by both chemical and enzymatic methods, the first one using concentrated nitric acid and the second proteinase K. Diatoms were present in most organ samples of the immersed corpses; no diatoms could be found in the control samples. Our experience was that the enzymatic method seemed to be more convenient in terms of rapidity, safety and environmental protection than chemical digestion. The number of diatoms recovered with both methods was similar. Qualitative and quantitative analysis of both water and organ samples of immersion cases supported the diagnosis of death by drowning in 41.6% of the putrified cases studied. The authors suggest that diatom analysis using enzymatic digestion of organs can be used as a criterion for positive diagnosis of drowning in cases involving putrified bodies.