This paper describes results of a population study of two X-linked STR microsatellite markers: DXS7108 and DXS1196. 298 samples of DNA of unrelated persons (male and female) from the Northern part of Poland were analyzed. DNA was isolated using a non-enzymatic method. After amplification PCR products were separated by means of capillary electrophoresis using the ABI PRISM 310 Genetic Analyzer. The most common alleles of each locus were sequenced and used as a control ladder to type unknown samples. Testing for Hardy-Weinberg equilibrium (HWE) showed no significant deviation for these two loci. Statistical parameters (PD, HET, MEC) showed that examined systems are useful in forensic medicine.