The Y chromosome STRs DYS437, DYS438 and DYS439 were selected from publicly available genome databases and used to analyse an Italian population sample. A tetraplex PCR reaction including the highly informative DYS385 locus, was set up and used for the analysis of 131 male samples to determine allele frequencies and STR diversity values. The number of different haplotypes and the haplotype diversity value found from the analysis of the STRs included in the tetraplex reaction were very similar to those found from the analysis of the basic set of 7 Y-STRs (DYS19, DYS389I/II, DYS390, DYS391, DYS392 and DYS393) previously carried out on the same population sample. By combining the allelic states of the 11 Y-chromosomal STRs we could construct highly informative haplotypes that allowed the discrimination of 93.8% (120 out of 128) of the samples tested. This approach represents a very powerful tool for individual identification and paternity testing in forensic medicine.