In forensic studies of death issues, the body of victims have been found in the water, and by using the diatom test, it could be determined whether the cause of death is related to drowning or not. One more critical problem occurs, when the victim was killed and thrown into the water, was he/she alive at the time of drowning? Therefore, the diatom species in the water of six different sites from two canals (Mit-Yazid and Tanbara Haweis canals, the Delta region, El-Gharbia government, Egypt) were analyzed and the physicochemical parameters for these sites were measured to diagnose the cause of death of ten cases found in the studied canals, and determining the accurate site of death. In the present research, the water samples from six different sites of Mit-Yazid and Tanbara Haweis canals were collected during the time of victim collection in 2021. The diatom frustules were extracted by the acid digestion of the lung tissue of the ten cases, and from the water samples of the studied canals according to the standard methods of diatom separation. A total of 65 diatom species belonging to 31 genera were recognized from the water samples of Mit-Yazid and Tanbara Haweis canals and the lung tissue of ten victims, which included 5 males, 3 females, and 2 children aged between 5- 63 years. The relative abundance of the recognized diatoms varied between the studied sites. The reports indicated seven positive cases of drowning and three negative cases. The results obtained in this research may attain an exact clarity of the obscurities related to the death linked to drowning and can be helpfully used as reference data for verifying the correct site of drowning.