Introduction: Leucas aspera is one of the important medicinal plants in Indian medical system and it belongs to Lamiaceae family. Leucas aspera (Willd) Link (L. aspera) belongs to Leucas genus, widely distributed throughout India. L. aspera has many vernacular names and is commonly known as Thumbai. Flavonoid is a phenolic compound which is widely distributed in the plants and responsible for many biological activities. Preliminary phytochemical analysis gives a broad idea to the researchers for their further research. Methods: In this present study, we did a preliminary phytochemical screening, quantitative estimation of total flavonoids and fingerprinting profile of flavonoids compounds using five different solvent extracts obtained from leaves of L. aspera. Results: Preliminary phytochemical screening confirmed the presence of flavonoid compounds in L. aspera. Higher concentration of total flavonoid compounds was noted in ethanol extract compared to petroleum ether, chloroform, isopropyl alcohol and ethyl acetate extracts. A densitometric high performance thin layer chromatography (HPTLC) study showed more number of flavonoid compounds are present in ethanol extract compared to other solvents. Conclusions: Results of this study revealed, L. aspera leaf is a rich source of flavonoid content and it can be used to alleviate many chronic illness and various diseases. This study results warrants for further isolation, identification and characterization of active principle which is responsible for the biological activity.