DNA technology has entered our lives in every field as one of the most important scientific developments of this century. DNA analysis: It is widely used to identify suspicious persons in various forensic crimes, to identify unidentified corpses who died due to mass disasters and other reasons. In such cases, unsatisfactory results can be obtained from DNA analysis performed on rotten and decaying tissue samples taken from unidentified corpses coming from the crime scene to the forensic laboratories. This may be due to DNA contamination. The most common causes of DNA damage are enzymes secreted by microorganisms found in the corpse and environment. Microbial enzymes cause DNA damage, insufficient or no PCR amplification, thus irregularities in the peak levels in the DNA electropherogram and the appearance of meaningless and missing peaks. When DNA analysis methods are applied to a postmortem biological sample in which microorganisms multiply, it may be difficult to obtain accurate and precise results due to degradation. The aim of this study is to evaluate the importance of identification of microorganisms (bacteria) that reproduce in postmortem muscle tissues in terms of forensic sciences, to determine whether they prevent DNA analysis, and if so, to determine which bacteria may cause it.