Integrons are mobile genetic elements which carry effective genetic factors in antibiotic resistance. These elements have several classes and play an important role in the development of antibiotic resistance in Gram-negative bacteria. Klebsiella pneumonia as Gram-negative bacteria caused a variety infection and increasing the antibiotic resistance of this bacterium leads to a majority of problems in its treatments. The present study was conducted to investigation of class I and II integrons among Klebsiella pneumoniae with focus on association with antibiotic resistance. In this cross sectional study, a total of 100 Klebsiella pneumoniae isolates were collected from hospitals of Semnan were identified by biochemical tests. Detection of antibiotic susceptibility was performed by disk diffusion method. For detection of class I and II integrons, PCR by integrase genes, intI and intII, were performed. A p value of <0.05 was considered statistically significant. The highest rate of resistance was observed for trimethoprim/sulfamethoxazole (49%), ceftriaxone (41%) and ceftazidime (40%) while only 10% of isolates showed resistance to imipenem. PCR for intI were positive in all resistance isolates (46%) and intII was positive in lower rate (40%). Overall a significant association was observed between the prevalence of integrons and resistance to antibiotics (p<0.05). This study demonstrated that integrons are widely prevalent and play an important role in multidrug resistance in Klebsiella pneumoniae isolates in this region.