In our previous study, we investigated Chenopodium album Linne (CAL) ethanol extract and its fractions on anti-gastritic actions using the HCl/ethanol and indomethacin induced gastric lesion model and Helicobacter pylori (H. pylori). Based on the results, butanol fraction was most effective among fractions obtained from CAL. This study aims to elucidate the mechanisms of butanol fraction, and betaine as a constituent of the butanol fraction, on gastritis and anti-gastric cancer cell growth. First, we examined antioxidant properties using hydrogen peroxide and superoxide radical, and we found that butanol fraction and betaine may be good antioxidants. Second, cytotoxicity was assessed by measuring cell viability and 4,6-diamidino-2-phenylinodole dihydrochloride (DAPI) staining of human gastric cancer cells (AGS cells). We also examined the relationship between the cytotoxicity and intracellular $Ca^{2+}$ signaling mechanism. The butanol fraction demonstrated cell viability 71.49% at the concentration of 100 ${mu}g/ml$ and increased intracellular $Ca^{2+}$ concentration in a dose dependent manner. Finally, we observed the mucus content as a defensive factor and gastric secretion as an aggressive factor, and found that the mucus content noticeably increased when treated with butanol fraction and betaine and gastric secretion decreased when treated with betaine in vivo study. From these results, we suggest that CAL butanol fraction and betaine may have protective effects on gastritis.