The study was organized to investigate the anomalous methylation of genes NA?1, RASSF1A, MLH1, N33, DAPK, the expression of genes hTERT. metalloproteinase MMP7, MMP9, survivin. COX-2, p53. The activity of telomerase in 106 samples of stomach tumors taken through intra-operation way and 53 samples of stomach tumors taken through endoscopic way and 50 samples of biopsy taken from patients with chronic calculous cholecystitis (comparison group) was analyzed too. These changes can be used as additional markers both in diagnostic of cancer of stomach and dynamic monitoring of operated patients.