Allele and haplotype frequencies of five chromosome STR loci (CD4, TPO, FES, TH01 and VWA) were determined for unrelated males throughout Portugal. This report presents STR data for three separate regions of Portugal, being the first time that data on the south of the country is presented. This study reveals that the three regions from Portugal are not genetically homogeneous. The north of Portugal presents significant differences in the CD4 locus, when compared with the other two populations. When compared with Madeira and Açores, the three regions show a different behavior at TPO and VWA loci.