Introduction: Succesful isolation of DNA is the basis for forensic DNA profiling. DNA can be obtained from variety of biological samples collected at the crime scene; such as blood, saliva, epithelial cells, semen etc. Choosing a suitable method for DNA extraction requires consideration of many factors, since every method has its advantages and limitations. Those methods are divided into two main groups; namely solution- based DNA extraction methods and solid-phase DNA extraction methods. The Chelex® 100 and the QIAamp®Investigator Kit protocols are the examples of the latter. Materials and methods: Six biological samples of human origin collected from three different donors were analyzed. In order to investigate their efficiency DNA isolation was performed using two different protocols: Chelex and the QIAamp Investigator Kit protocol. The isolated DNA was amplified by PCR reaction, and the results were visualized after gel agarose electrophoresis using a UV transilluminator. Results and Discussion: DNA was successfully extracted from all samples tested using both Chelex and the QIAamp Investigator Kit extraction protocols. Samples to which no distilled water was added to the PCR mix showed a higher fluorescence intensity of the sample "bands" after agarose gel electrophoresis. Chelex method is more cost and time- effective but less effective in removal of PCR inhibitors compared to QIAamp Investigator kit isolation). Conclusion: Both methods are effective in isolating DNA from biological samples commonly found at the crime scene. The DNA samples extracted with Chelex method showed higher fluorescence intensity of "bands" after gel electrophoresis in comparison to those extracted using QIAamp Investigator Kit, indicating higher DNA concentration.