The present work includes a simple, economic, rapid, accurate and precise UV spectrophotometric and isocratic RP-HPLC method development for estimation of Lenalidomide in bulk and its formulation. Estimation was done at 250nm which was found to be λmax of Lenalidomide. The simple, selective, isocratic RP-HPLC method for Lenalidomide was developed on reverse phase C18 waters column (4.6 mm x 250 mm, 5μm ) with a mobile phase of acetate buffer (20 mM ) (pH 5): Methanol = 85:15 at a flow rate of 1ml/min and detection wavelength 250nm. The developed methods were validated successfully according to ICH Q2 (R1) guidelines. Both the spectrophotometric and chromatographic methods showed a good linear response with r2 values of 0.998 and 0.9986 respectively. The percentage relative standard deviation for both methods was found to be less than two, indicating that the methods were precise. The mean percentage recovery for UV method was between 99.2% and for RP-HPLC method was 99.6% respectively. From the results it could be concluded that both the developed methods were specific, selective and robust. The methods could be successfully applied for analysis of capsule formulation of Lenalidomide.