Background/Aims: Gastric cancer (GC) is the second most common malignancy worldwide, with a high mortality rate. The incidence of GC has declined in the western countries during the last decades. The glutathione S-transferases comprise a group of enzymes that are critical in the detoxification of carcinogens. In this study we aimed at the relationship GSTP-1 methylation in patients with intestinal metaplasia with and without Helicobacter pylori infection, gastric cancer and controls. Methodology: The methylation status of GSTP1 gene was analyzed by methylation specific PCR after bisulfate modification in H. pylori (+) (n=25) and (-) (n=25) intestinal metaplasia (IM) patients, GC (n=25) and control subjects (n=15) between September 2009 to November 2011. Results: During the study period 90 patients who underwent endoscopic examination were included in the study. When we considered the GSTP1 gene methylation profile in all of the groups; 26 (28%) patients had methylated GSTP1 gene, 31 (34%) patients had unmethylated GSTP1 gene and 33 (36%) patients had heterogeneously methylated GSTP1 gene. Conclusions: GSTP1 gene methylation profile is not appropriate for early diagnosis of cases with gastric cancer.