Objective: The CYP2D6 enzyme shows a wide range of polymorphisms. It is responsible for the metabolism of substances such as opiates that have a great importance in forensic sciences. However, some mutations damage the activity of this enzyme and cause interruption in metabolism of the drugs which may lead to unexpected adverse drug reactions, even to death. Although many studies have dealt with CYP2D6 polymorphism, there is no research concerning CYP2D6 enzyme polymorphism and opiate dependence in our country. Material and Methods: We aimed to investigate the single nucleotide polymorphisms of CYP2D6*3, *4 and *6 alleles. Forty nine opiate addicts and 34 control samples were studied using tetra-primer polymerase chain reaction (PCR) technique in a single tube and by dividing the protocol into two steps. Results: CYP2D6*4 and CYP2D6*6 alleles frequencies were determined as 0.082 and 0.031, respectively, however no significant result was obtained for CYP2D6*3. Allele and genotype frequencies of CYP2D6*4 and *6 for both opiate addicts and control group were in concordance with the Hardy-Weinberg equation. Conclusion: We suggest that detection of CYP2D6 polymorphism may clarify the sudden-unexpected deaths due to intoxication of opiate addicts and some negative autopsy cases related to medical or illicit drugs.