Because Lonicerae Flos has effects of antiinflammatory and antioxidant, we studied an effect of Lonicerae Flos on reflux esophagitis (RE) through those effects. Rats were treated with three different dosages of LF (500, 250 and 125 mg/kg) orally for 14 days before pylorus and forestomach ligation. Six hrs after pylorus and forestomach ligation, we dissected a stomach and examined a stomach volume, gastric acid output, pepsin release in the stomach, total hexose, sialic acid in stomach tissue and histamine contents of sera. The results were compared with an ${alpha}$-tocopherol (once orally, 1hr before operation, 30 mg/kg) treated group in which the effects on RE were already confirmed. Lonicerae Flos extract (LE) reduced gastric volumes compared to RE control. This indicate that LE protect a stomach mucosa by depressing of gastric acid release and corresponse with a reducing histamine content of serum. And LE decreasd a volume of pepsin in stomach compraed to RE control, LE increased contents of total hexose and sialic acid based on esophageal and gastric mucus. This indicated that an increased mucus by LE protected inflammation of esophagus mucosa and gastric mucosa induced by gastric acid. So, LE suppressed a gasric acid by decreasing a pepsin release in stomach, suppressed an injury of esophagus inducted by gastric acid with increasing esophageal mucus and a minimum dose of LE to RE was 250 mg/kg. The results suggest that antioxidant effects of LF could attenuate the severity of reflux esophagitis and prevent the esophageal mucosal damage, and validate its therapeutic use in esophageal reflux disease.