A new, accurate, precise, highly sensitive and robust RP-HPLC method for the quantitative estimation of Nimbin in bulk and pharmaceutical dosage form has been developed and validated as per ICH guidelines. This method was carried out on an Agilent 1200 series  (250 mm x 4.6 mm, 5 μ) C18 column packing by using isocratic mobile phase consisting of Acetonitrile - Water (90:10 v/v) at ambient temperature. The flow rate was set to 1.0 ml/min with UV detection at 214 nm with run time 5 min and injection volume set at 10 μl. The retention time of Nimbin was 2.853 min. The linear regression analysis data equation (Y = 40,520.83 x 45,074.11) from the calibration curve showed a good linear relationship with a correlation coefficient of 0.9999. The concentration ranges were 6.25-200 μg/ml. The limit of detection and limit of quantification were 0.011μg/ml and 0.034μg/ml respectively. The percentage of RSD for precision and accuracy of the method was found to be less than 2%. The percentage recovery of Nimbin was found to be 98.50%.  The developed method was validated in terms accuracy, precision, robustness and recovery. This selective method is found to be accurate, repeatability and effectively used for the Nimbin in marketed sample with better chromatographic conditions.