]. In the present study, six bacteria species were isolated from external body surface of American cockroaches. Klebsiella spp. and Pseudomonas spp. were found the maximum bacteria species, respectively. Meanwhile, Proteus spp, and Streptococcus spp. were found the minimum bacteria species from the cockroaches’ external body surface. In Nejati’s investigation, 12 bacteria species were extracted from American cockroaches’ outer body surface. E. coli (40%) and Staphylococcus epidermis (20%) obtained the most[3].