In the introductory part of this thesis, a historical review of DNA methodology, technology and its acceptance as a relevant evidence in criminal investigations and judicial authorities has been presented. The aim of this thesis is to demonstrate methods of DNA analysis in forensics and to describe and compare multiplex systems for genetic loci analysis. In thesis we will also show advantages and disadvantages and make usage recommendations for particular system. In the end of the thesis is an overview of the most renowned DNA databases in the world and the explanation of their association with multiplex systems for analysis with goal to emphasize their importance and importance of data exchange among them. The discovery of the polymorphisms described by the eukaryotic genome has prompted the development of DNA profiling based on the use of certain molecular markers, mostly STR, but also by VNTR and SNP markers. The ultimate DNA profiling result is shown by the electropherogram, set of markers (loci) of the selected commercial set of the multiplex system, with the associated peaks representing alleles. The discovery of the polymorphisms described by the eukaryotic genome has prompted the development of DNA profiling based on the use of certain molecular markers, mostly STR, but also by VNTR and SNP markers. The ultimate DNA profiling result is shown by the electropherogram, set of markers (loci) of the selected commercial set of the multiplex system, with the associated peaks representing alleles. The methods of basic multiplex DNA analysis systems, the most autosomal STR systems of three corporations (Promega, Applied Biosystems, Qiagen), as well as sex STR markers (X and Y multiplex systems), mtDNA and miniSTR systems are described. The results have shown that selecting a particular commercial multiplex STR system for DNA profiling depends most on the sample quality as well as the circumstances for which profiling is performed. Most autosomal multiplex STRs are used due to the possibility of co-amplification on a large number of loci and due to the significant high levels of discrimination and individualization. In cases of degraded DNA in a sample or samples that have failed due to the influence of external factors, the best choice is miniSTR systems or mtDNA. X-linked or Y-bound STR markers and mtDNA may be used for the purposes of genealogy and paternity or motherhood demonstration. DNA databases allow searching and storing of DNA profiles for the purpose of identifying perpetrators, missing and unidentified persons as well as the prevention of all forms of crime. Contained DNA profiles were made according to precise analysis instructions on certain loci that were selected in multiple multiplex systems.