Background: The aim of this study was molecular investigation of class 1 integron in drug-resistant Shigella strains isolated from clinical samples. Materials and Methods: 118 samples were collected from the West of Iran. The antibiotic susceptibility, the pattern of antibiotic resistance and investigation the int1 gene was conducted. Results: From 118 samples taken, 27.12% samples were confirmed as Shigella. Also, 62.5, 21.875, 9.375 and 6.25% as S. sonnei, S. flexneri, S. boydii and S. dysenteria were known, respectively. The highest sensitivity was related to carbapenem and tetracycline (97%) and Shigella has the most resistant to ampicillin (94%). Also, 14 samples (44.8% of the isolates) were found to be positive for the presence of integrase gene. This association was significant for S. flexneri and integron 1 (P = 0.0001). Conclusion: Carbapenem and tetracycline were the most effective antibiotics. There was also a significant association between integrase 1 gene and MDR strain (P = .00001).