Materials and Methods: Urinary tract infection (UTI) is one of the most common bacterial infections in childhood, older adults and women. Since the delay in diagnosis and proper treatment could lead to irreversible complications including renal failure, appropriate treatment is required immediately after the diagnosis of such infections. So because of antibiotic pattern difference in each region, frequency of UTIs pathogens and E.coli susceptibility pattern have been done in Salmas city.
  Results: This cross-sectional study was carried out on 573 patients with UTI which referred to reference laboratories in Salmas city; 396 and 177 out of 573 were female and male respectively. Mid-stream urine samples taken from patients were cultured in Blood and EMB agar. All isolates were identified and confirmed by standard biochemical tests. Antibiogram was done by disk diffusion (Kirby-Bauer) for E.coli isolates on Muller –Hinton agar based on CLSI guidelines.
 Conclusion: According to the result of this study, E.coli was the most common pathogen of urinary tract infections, and nitrofurantoin, ceftriaxone, amikacin, and nalidixic acid were recognized as the most effective antibiotics against E.coli, respectively. E.coli showed the highest resistance to ampicillin and cotrimoxazole, which requires the health professional's attention and further studies