the largest value of postmortem submersion and control group)were found in the lung sample The main species of diatoms found in the water sample and drowninga nimals were the same; 3.There was no significant difference of diatom both quantitative and qualitative between postmortem submersion and control group;4. There was no diagnostic value of the diatom analysis for the liver or kidney. A favorable result was obtained in a case of drowning victim of human being submerged in the reservoir for two days examined by the same method,it showed that the conclusionof our study could be used in the forensic medicine practice