Mutation analysis in keratins 5/14 (K5/14) had been performed in five Polish families with epidermolysis bullosa simplex (EBS) to extend genotype-phenotype correlation and to add to the mutation database. All the patients had been clinically classified into two subtypes of EBS; Weber-Cockayne (EBS-WC) and Dowling-Meara (EBS-DM) as well as one case of EBS with mottled pigmentation (EBS-MP). DNA from patients and their family members was assessed for mutations in K5 or 14 using polymerase chain reaction amplification and subsequent direct sequencing. We identified four different missense mutations in K5 and one missense mutation in K14. Three of these are novel. Mutations associated EBS-DM resided in the highly conserved 20 amino acids end of the 1A domain in K5. Direct nucleotide sequencing of a case of EBS-MP revealed a heterozygous P25L mutation in K5. However, no genotype-phenotype correlation was identified in families with EBS-WC. The present study demonstrates the first series of molecular genetic data in EBS from Poland.