<p>Background: Growing antibiotic resistance among urinary opportunistic pathogens such as <em>Klebsiella pneumoniae (K. pneumonia)</em> has created a worrisome condition in the treatment of the Urinary Tract Infections (UTIs) in recent years. Integrons play a significant role in the dissemination of antibiotic resistance genes. The present study was conducted to investigate class 1-3 integrons and the corresponding resistance gene cassettes in urinary <em>K. pneumoniae</em> isolates.</p> <p>Methods: In this study, from December 2015 to September 2016, a total of 196 <em>K. pneumoniae</em> isolates were collected from the patients with UTI referred to medical diagnostic laboratories in Yasouj, Southwestern Iran. Antibiotic susceptibility patterns of isolates were determined using 12 antibiotics by the disc diffusion method. Polymerase Chain Reaction (PCR) was used for detection of integron genes (<em>intI1</em>, <em>intI2</em>, and <em>intI3</em>). The variable regions of integrons were amplified by PCR and sequenced to identify the corresponding gene cassettes.</p> <p>Results: Thirty-nine different antibiotic resistance profiles were observed among <em>K. pneumoniae</em> isolates. Only 12.2% of <em>K. pneumoniae</em> isolates were found to harbor the <em>intI1</em> gene. While 17 (60.7%) out of 28 Multidrug Resistance (MDR) <em>K. pneumoniae </em>isolates carried the <em>intI1</em> gene, only 4.2% of non-MDR isolates harbored <em>intI1</em> gene. Totally 7 different gene cassette arrays were found in the <em>intI1</em> gene of <em>K. pneumoniae</em> isolates. The <em>aadA1 </em>was the most prominent gene cassette. Also, high frequency of <em>dfrA</em> containing gene cassettes was observed.</p> <p>Conclusion: Continuous monitoring and characterization of integrons and their associated gene cassettes could be helpful in controlling the rising rate of antibiotic resistance.</p>