Background: High-performance liquid chromatography is one of the major analytical techniques used in the quality control of phytochemicals. Objective: This research article presents the development of HPLC method to detect and quantify the major marker components, kaempferol, and quercetin from four plant species. Materials and Methods: HPLC method was developed for the qualitative and quantitative analysis of plant extracts by using orthophosphoric acid and methanol (95:5) at 370 nm for kaempferol, methanol and orthophosphoric acid (60:40) at 262nm for quercetin. Results: Kaempferol was detected from the hydro alcoholic extracts of Talinum portulacifolium leaves (RT 13.720, concentration 1.08 mg/ml) and flowers of Gomphrena serrata (RT 13.758, concentration 2.13mg/ml). Kaempferol was reported for the first time from Gomphrena serrata. Quercetin was separated and identified from the hydro alcoholic extracts Alternanthera sessilis stems (RT 6.503, concentration 0.01mg/ml). The hydroalcoholic extract of Euphorbia heterophylla stems (RT 6.588, concentration 0.01mg/ml) was also evaluated for the presence of quercetin. Conclusion: The method developed is very useful tool for qualifying and quantifying the plant specimens as well as their extracts.