Barleria prionitis Linn is an herbal plant from Acanthaceae family used in treatment of wide variety of diseases and disorders. Different phyto constituents like quercetin, catechol and tannic acid are expected to be present in the plant leaf. However, to date, there is no analytical method development or validation pertinent to for simultaneous quantification of quercetin, catechol and tannic acid in Barleria prionitis Linn leaf extract. The objective of this work was to develop asensitive RP-HPLC method for simultaneous estimation of quercetin, catechol and tannic acid in 70% ethanol extract of Barleria prionitis Linn leaf. The analytes were separated by a 5 µm C18 column (4.6× 150mm), methanol: 0.1% orthophosphoric acid (pH: 2.4)(60: 40 v/v) mobile phase and analyzed at 40±0.5 C. The method had a flow rate of 0.5 ml min-1 and the three phytochemicals were detected at 275 nm using a PDA detector. The method was validated by ICH Q2 R1 guidelines. A linear relationship of peak area was established with the concentration range of 0.1-100 µg/ml. The method was found to be specific, accurate and precise (% RSD< 2%). The method showed negligible changes in the responses when the chromatographic conditions were altered and thus proved to be robust. Thus, the novel RP-HPLC method was proven to be quite effective, reliable and can be applied for simultaneous estimation of quercetin, catechol and tannic acid in Barleria prionitis Linn leaf extract.