Identifiler is one of the most useful multiplex systems for standard paternity testing. But in some cases the mother is unavailable for testing and there can be a problem with obtaining sufficient value of probability of paternity. One hundred and fifty excluding cases and 150 including ones were analysed to check the validity of Identifiler for analysis of standard as well as motherless cases. Power of exclusion and paternity index were analysed for each locus as well as for the entire set of the 15 STR markers. Our researches confirmed the usefulness of Identifiler system for standard paternity testing, and showed that the motherless cases need to be examined more widely.