The word forensics has roots in the Latin language, and was applied to the forum where all the facts related to a crime were discussed. After the conclusion of the discussion, the fate of the suspects is laid out. The beginning of development of forensic science was associated with the development of Chinese medicine. “Hsi Duan Yu” was the first document that speaks about forensic. The book has described the application of knowledge in forensic entomology in solving crimes. As people throughout history increasingly understood the relationship of insects and corpses, the development of forensic entomology was improved. The study of development and growth of different insect species larvae, which lay out from eggs left on the corpse soon after death, a forensic entomologist with the knowledge of structure and life cycles of insects can determine the time of death with accuracy within one day. One of the most important species for determining the post-mortal interval is Chrysomya megacephala, the family Calliphoridae, which comes on the body several minutes after death, and lays eggs. Determining the exact time of death excludes suspicious people who do not have a confirmed alibi. Also, it allows investigators to determine whether someone was with the victim during the period in which there was a murder. Most important thing on the crime scene is to carefully and slowly collect evidence such as larvae, pupae and adult forms of insects. Each sample is a valuable and it is necessary to preserve, document and collect it, in order not to destroy any valuable evidence. Many murder cases were sometimes difficult to solve without a witness or finding the corpse shortly after the crime, but today it is successfully resolved by cooperation of scientists from different fields. People should never get used to death and violence so that it no longer surprises or affects them. Therefore, it is important that the forensic sciences assist in solving crimes and continue to develop.