Abstract Diatoms are single-celled photosynthesising eukaryotic algae having great importance ecologically and forensically. They have a siliceous skeleton (frustule) and are found in almost every aquatic environment including fresh and marine water bodies. This review attempts to study the diatom ecology in the water bodies of Rajasthan. Diatoms are found in the body of the drowned individual and can be used as corroborative evidence in cases to answer the questions like the site of drowning, time of drowning, ante-mortem or post mortem drowning. It can also be served as reliable proof of site and time of drowning, even in the cases of contamination due to immersion of the body into the water for a longer time. This review study revealed that the most common diatoms reported in the waterbodies of Rajasthan belong to species Navicula, Nitzschia, Cyclotella, Synedra, Fragilaria, Gomphonema whereas some site specific diatom’s species are also reported like Stauroneis in Kaylana lake of Jodhpur, Brachysira in Chambal river, Kota, Achnanthidium in Chambal river, Kota and Maavath pond (Jaigarh fort), Anomoeneis in Indira Gandhi Canal, Hanumangarh.