Background: Pseudomonas aeruginosa infection is one of the major challenges in burn patients. This organism is resistant to a wide range of antibiotics. The aim of this study was to investigate the antibiotic susceptibility and genetic relatedness in Pseudomonas aeruginosa isolated from patients admitted to Motahari Burn Center, Tehran, Iran. Methods: This study was conducted on 186 burn patients with Pseudomonas aeruginosa colonization following admission in Motahari Burn Center during one year. Antibiotic resistance test was performed by disc diffusion method and genetic relatedness was evaluated by PCRRAPD analysis. Results: The highest and lowest percentage of resistance was observed against ceftizoxime and ciprofloxacin. The genotyping study by RAPD PCR technique revealed 57 different genotypes, among which RAPD 5, RAPD 8, and RAPD 9 were the most prevalent patterns and produced by 14%, 9%, and 7% of the isolates, respectively. Conclusion: In total, no association was found between RAPD genotypes and antibiotic resistance patterns, and death rate.