The pH of betel leaf extract was determined with sterile pH paper strip. At 10% concentration, pH of the extract was recorded 7.0. From the stock (200mg/ml) solution 10mg/ml of ethanol extract of pH 5, 7, 9 and 10 were prepared by adding measured amount of extract in buffer. Negative control of ethanol (without betel leaf extract) was prepared in buffers at different pH. The antibacterial activity of the ethanol extracts at different pH was carried out against the test organisms were done by the disc diffusion method.