UV Spectrophotometric method has been developed for estimation of lamivudine in bulk and tablet dosage form by using water as solvent. Method developed is Area Under Curve (AUC) method. For analysis of lamivudine by AUC method the wavelength range selected was 265 nm to 275 nm because the linearity was obtained within this area with good reproducibility of results. Lamivudine shows absorbance maxima (λmax) at 271 nm scanned in UV range of 400 nm to 200 nm. Lamivudine obeys Beer’s law in the concentration range of 10-60 μg/ml.