Prostate cancer is an important type of cancer in males with the highest mortality rate after the lung cancer, especially in industrialized countries. RAS oncogenes, originating from proto-oncogenes with point mutations, play an important role in cancer cell proliferation. The RAS proto-oncogene mutations occur in 25% of human cancers. The aim of the study was to investigate the potential mutation of KRAS gene at exon 2 (codons 12/13), exon 3 (codon 61) and exon 4 (codon 117/146) in Turkish patients with prostate cancer. The case group was comprised of 45 paraffin-embedded prostate cancer tissues. The control group was comprised of 20 healthy samples. The mutation analysis was performed by using PCR-based High Resolution Melting (HRM) analysis. The DNA samples of case and control groups were isolated and evaluated by HRM. Chi-square and Fisher's exact tests were used to evaluate the relationship between mutations in KRAS gene and prostate cancer. p<0.05 was considered as statistically significant. There were mutations in exon 2 (1 patient) and exon 3 (3 patients) of KRAS. In exon 4, no mutations were determined. The results of this study suggest that exon 2 and exon 3 mutations in KRAS gene may be effective in the development of prostate cancer. In addition, the results of this study may provide insight into the efficacy of anti-EGFR treatment on cases without KRAS mutation.