Proteus mirabilis isolates (n = 177), collected between 1996 and 2000 in four hospitals in the West Pomeranian area of Poland, were characterized by antibiotype and pulsed-field gel electrophoresis (PFGE). The selected isolates were collected from different wards (intensive care unit, surgery, internal medicine, and urology). The strains were cultured from various specimen types, mostly from urine, wound samples, bronchial exudates and sputa. The identification was done by biochemical test ID 32E ATB (bioMerieux). Analysis of PFGE patterns was based on comparison of the banding patterns obtained by PFGE of chromosomal DNA digested with SfiI enzyme. Among all P. mirabilis isolates tested three major genotypes A (A1-A7), B (B1-B4), C (C1-C5) and 71 unique patterns were identified. The same genotypes were obtained from different patients, treated in different wards and hospitals during a 5-year period. The strains which belonged to the genotypes A and B were multiresistant and most of them produced ESBL; genotype C was more sensitive to antibiotics.