Proteus mirabilis is a common etiologic agent of urinary tract, burn wound and diabetic foot infections. Resistance to Proteus mirabilis is also common and represents a challenge to antibiotic therapy. This study aimed to investigate the antibiotic resistance of Proteus mirabilis isolated from three sources; urinary tract infections, burn wound infections in addition to diabetic foot infections. Forty-five clinical isolates of Proteus mirabilis (15 from each source) were used in this study. Complete resistance was found with each of ampicillin and tetracycline. High resistance was exhibited with cefepime. The resistance was intermediate against ceftazidime, cefotaxime, sulfamethoxazole-trimethoprim, amoxicillin-clavulinic, chloramphenicol, cefoperazone, aztreonam and ampicillin-sulbactam. Low resistance was found with piperacillin. These low resistance rates were also shown against tested aminoglycosides and fluoroquinolones. Very little resistance was found to imipenem, while no resistance was exhibited against piperacillin- tazobactam. The resistance pattern showed variation among different sources. Generally, burn wound isolates showed the highest resistance rates followed by diabetic foot isolates, while urinary tract isolates were the least resistant. High resistance was found with cefepime only in isolates from urinary tract infections and no diabetic foot isolate was highly resistant to any of the tested antibiotics. However, such resistance was observed with amoxicillin-clavulinic acid, cefepime, ceftazidime, cefotaxime and sulphamethoxazole-trimethoprim in burn wound isolates. Multidrug resistance (MDR) was also found with varying rates in isolates from different sources. MDR was more common in burn wound isolates than in diabetic foot isolates or urinary tract isolates. This study suggests that there is a variation in antibiotic resistance of Proteus mirabilis among different sources and alarms against high resistance especially in burn wound isolates that requires a strict policy in antibiotic dispensing to minimize such tesistance.