High performance thin layer chromatographic (HPTLC) method has been developed and validated for simultaneous investigation of Irbesartan and Hydrochlorothiazide in tablet formulation. Chromatographic separation was performed on aluminium plates precoated with silica gel 60F254, with methanol: ethyl acetate (7: 3 % v/v) as mobile phase. Detection was performed densitometrically at 254 nm. The Rf values of Irbesartan and Hydrochlorothiazide were 0.24 ± 0.10and 0.42 ± 0.06, respectively. Linearity was found to be in the concentration range of 150-900 ng/spot for Irbesartan and 25- 150 ng/spot for Hydrochlorothiazide, accuracy (100.05 % for Irbesartan and 100.26 % for Hydrochlorothiazide) and specificity, in accordance with ICH guidelines. The method can be used for routine analysis of Irbesartan and Hydrochlorothiazide in tablet formulation.