This study was undertaken to investigate changes in blood pressure and heart rate in normal cats by administration of Korean native green tea. The chemical components of Korean native green tea which determined are water(2.2%), water extract(32.7%), vitamin C(480%), caffeine(2.6%), tannin(32.7%) and amino acid of water soluble content 5.8%. Effect on blood pressure in administration 100mg/kg, 300mg/kg, 500mg/kg of extract of green tea, the mean depressor response is 44.8$pm$3.3mmHg, 60.5$pm$3.6mmHg, and 65.0$pm$3.3mmHg in normal cats. Effect on heart rate in administration 100mg/kg, 300mg/kg of extract of Korean native green tea, the mean decreased heart rate is 2.8$pm$4.5 beats/min, 15.2$pm$6.4beats/min and 19.1$pm$4.0 beats/min.