A simple UV-Visible spectrophotometric method has been developed for the determination of Atorvastatin in its pure form as well as pharmaceutical dosage form using Methyl Orange reagent. The method is based on the measurement of absorbance of Atorvastatin in methanol at 410 nm. The Beer’s law is obeyed over the linear range 50-300μg /ml of Atorvastatin. All the variables were studied to optimize the reaction conditions. No interference was observed in the presence of common pharmaceutical excipients. The validity of the method was tested by analyzing the drug in its pharmaceutical preparations. Good recoveries were also obtained. Assay for the tablet preparation was performed using UV-Visible spectrophotometric method and the results were found to be within acceptable limits.