Background: In the current study, 23 species within 18 genera and 13 families of order Diptera were taxonomically studied. These members were collected from, on, in, around and beneath the carcasses of rabbits and guinea pigs. Results: The families which collected from the carcasses are as follows: Agromyzidae (one subfamily, one genus and only one species), Calliphoridae (three subfamilies, three genera and sex species), Dolichopodidae (one subfamily, one genus and only one species), Drosophilidae (one subfamily, one genus and only one species), Ephydridae (one subfamily, one genus and only one species), Fanniidae (one genus and only one species), Muscidae (two subfamilies, three genus and four species), Phoridae (one subfamily, one genus and only one species), Piophilidae (one subfamily, one genus and only one species), Psychodidae (one subfamily, one genus and only one species), Sarcophagidae (two subfamilies, two genera and three species), Sphaeroceridae (one subfamily, one genus and only one species), and finally Ulidiidae (one subfamily, one genus and only one species). Only seven of which (Calliphoridae, Fanniidae, Muscidae, Phoridae, Piophilidae, Sarcophagidae and Ulidiidae) are of forensic importance or necrophagous. Other families are the following: Drosophilidae, Psychodidae, Agromyzidae, Dolichopodidae, Ephydridae, and Sphaeroceridae are of minor importance as forensic indicators. Conclusions: Taxonomic keys for the adults which collected from the carcasses were constructed. Also diagnosis, synonyms, photographs and the forensic importance for the taxa were provided.